NEW: secondary axes: added functionality to manage additional secondary axes in a JKQTPBasePlotter and to select which x-/y-Axis to use for drawing a JKQTPPlotElement, see also issue #87

doc/CMakeLists.txt

@@ -180,6 +180,7 @@ if(JKQtPlotter_BUILD_EXAMPLES)
         rgbimageplot_qt/rgbimageplot_qt,rgbimageplot_qt_upsidedown/--iteratefunctorsteps
         mandelbrot
         geo_coordinateaxis0
+        second_axis/second_axis,second_axis_hor
         #speed
     )
 
@@ -207,6 +208,7 @@ if(JKQtPlotter_BUILD_EXAMPLES)
         impulsesplot/JKQTPImpulsesVerticalGraph,JKQTPImpulsesVerticalGraph_Symbols,JKQTPImpulsesHorizontalGraph,JKQTPImpulsesVerticalErrorGraph,JKQTPImpulsesHorizontalErrorGraph,JKQTPImpulsesVerticalGraphNoBaseline,JKQTPImpulsesVerticalGraph_SymbolsNoBaseline,JKQTPImpulsesHorizontalGraphNoBaseline,JKQTPImpulsesVerticalErrorGraphNoBaseline,JKQTPImpulsesHorizontalErrorGraphNoBaseline,JKQTPImpulsesVerticalGraphBaseline,JKQTPImpulsesVerticalGraph_SymbolsBaseline,JKQTPImpulsesHorizontalGraphBaseline,JKQTPImpulsesVerticalErrorGraphBaseline,JKQTPImpulsesHorizontalErrorGraphBaseline/--iteratefunctorsteps--smallscreenshotplot
         symbols_and_errors/JKQTPXYLineErrorGraph_JKQTPErrorBars,JKQTPXYLineErrorGraph_JKQTPErrorLines,JKQTPXYLineErrorGraph_JKQTPErrorPolygons/--iteratefunctorsteps--iteratefunctorsteps_suppressinitial--smallscreenshotplot
         boxplot/JKQTPBoxplotVerticalGraph,JKQTPBoxplotHorizontalGraph/--iteratefunctorsteps--iteratefunctorsteps_suppressinitial--smallscreenshotplot
+        second_axis/JKQTBasePlotter_addSecondaryYAxis,JKQTBasePlotter_addSecondaryXAxis
     )
 
 

doc/dox/examples_and_tutorials.dox

@@ -125,6 +125,9 @@ All test-projects are Qt-projects that use qmake to build. You can load them int
 <tr><td> \image html dateaxes_timeaxis_small.png
     <td> \subpage JKQTPlotterDateTimeAxes
     <td> `JKQTPXYLineGraph` and `JKQTPFilledVerticalRangeGraph` <br> C++ vector of data <br> date/time axes <br> plot min/max range graph <br> internal LaTeX parser <br> data from CSV files 
+<tr><td> \image html second_axis_small.png
+    <td> \subpage JKQTPlotterSecondaryAxes
+    <td> plottig with secondary axes, `JKQTPBasePlotter::addSecondaryXAxis()`/`JKQTPBasePlotter::addSecondaryYAxis()`
 <tr><td> \image html advancedlineandfillstyling_small.png
     <td> \subpage JKQTPlotterAdvancedLineAndFillStyling
     <td> `JKQTPXYLineGraph`, `JKQTPSpecialLineHorizontalGraph` and `JKQTPBarVerticalGraph` <br> C++ vector of data <br> advanced line styling and filling

doc/dox/jkqtplotter_naming.dox

@@ -18,6 +18,7 @@
            derived from JKQTPPlotAnnotationElement
       <li> \b key is the legend of the plot, showing a list of the graphs, each represented by a <b>entry marker</b> (showing the graphs color/symbol/...) and a <b>entry title</b>.
       <li> <b>coordinate axis</b> is each of the x- or y-axis (there might be addition axes, e.g. when showing a color-scale). Each coordinate axis is composed from several elements: the axis line itself, an <b>axis label</b>, axis <b> ticks</b> and corresponding <b>tick labels</b> (major and a second set of minor ticks in between are available)
+      <li> <b>secondary coordinate axis</b> you can add additional secondary x- and y-axes to a plot, which are shown stacked, beside the plot.
       <li> <b>zero axis</b>: a pair of axes through  the origin \c x=0 and \c y=0 of the coordinate system
       <li> \b grid a grid of horizontal/vertical lines, drawn behind the graph and providing visual guidance for the viewer of the graph. The grid is actually a part of the coordinate axes, as the lines are positioned at the same position as the axis ticks
       <li> <b>minor grid</b> in addition to the grid, corresponding to the major axis ticks, you can add additional lines that correspond to the minor axis ticks

doc/dox/todo.dox

@@ -29,7 +29,6 @@ This page lists several todos and wishes for future version of JKQTPlotter
     <li>plot: legend positioning as combination of 3 values: inside|outside + left|center|right + top|vcenter|bottom</li>
     <li>plot: refactor print preview/export preview code </li>
     <li>plot: rework layouting of legends: there are some inconsistencies/too large gaps ...</li>
-    <li>plot: secondary axes: independent and dependent (i.e. with transformation function from primary axis)</li>
     <li>sryling: better styling/more styling options for data-tooltips</li>
     <li>styling: color gradients as fill-styles in style-INIs</li>
     <li>styling: style.ini with glowing colors in dark background ("techno" or "cyberpunk")</li>

doc/dox/whatsnew.dox

@@ -67,6 +67,7 @@ Changes, compared to  \ref page_whatsnew_V4_0_0 "v4.0.0" include:
     <li>NEW: barcharts can be colored by a user-specified functor</li>
     <li>NEW: you can provide a custom draw functor to barcharts to completely customize their look</li>
     <li>NEW: barcharts and impulse graphs may now draw their baseline as stylable line (default: off)</li>
+    <li>NEW: secondary axes: added functionality to manage additional secondary axes in a JKQTPBasePlotter and to select which x-/y-Axis to use for drawing a JKQTPPlotElement</li>
   </ul></li>
   
   <li>JKQTMathText:<ul>

examples/CMakeLists.txt

@@ -91,6 +91,7 @@ add_subdirectory(rgbimageplot_opencv)
 add_subdirectory(rgbimageplot_qt)
 add_subdirectory(scatter)
 add_subdirectory(scatter_customsymbol)
+add_subdirectory(second_axis)
 add_subdirectory(speed)
 add_subdirectory(stackedbars)
 add_subdirectory(stepplots)

examples/second_axis/CMakeLists.txt

@@ -0,0 +1,34 @@
+cmake_minimum_required(VERSION 3.16)
+
+set(EXAMPLE_NAME second_axis)
+set(EXENAME jkqtptest_${EXAMPLE_NAME})
+
+message( STATUS "..   Building Example ${EXAMPLE_NAME}" )
+
+
+# Set up source files
+set(SOURCES second_axis.cpp )
+set(HEADERS  )
+set(RESOURCES  )
+set(UIS  )
+
+add_executable(${EXENAME} WIN32 ${SOURCES} ${HEADERS} ${RESOURCES} ${UIS})
+target_link_libraries(${EXENAME} JKQTPExampleToolsLib)
+target_include_directories(${EXENAME} PRIVATE ../../lib)
+if(JKQtPlotter_BUILD_STATIC_LIBS)
+    target_link_libraries(${EXENAME} JKQTPlotterLib)
+elseif(JKQtPlotter_BUILD_SHARED_LIBS)
+    target_link_libraries(${EXENAME} JKQTPlotterSharedLib)
+endif()
+
+# precomiled headers to speed up compilation
+if (JKQtPlotter_BUILD_WITH_PRECOMPILED_HEADERS)
+  target_precompile_headers(${EXENAME} REUSE_FROM jkqtptest_simpletest)
+endif (JKQtPlotter_BUILD_WITH_PRECOMPILED_HEADERS)
+
+
+# Installation
+install(TARGETS ${EXENAME} RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})
+
+#Installation of Qt DLLs on Windows
+jkqtplotter_deployqt(${EXENAME})

examples/second_axis/README.md

@@ -0,0 +1,135 @@
+# Example (JKQTPlotter): Barchart With Two-Color Fill-Mode {#JKQTPlotterBarchartsTwoColorFilling}
+This project (see [`second_axis`](https://github.com/jkriege2/JKQtPlotter/tree/master/examples/second_axis) shows how to plot with multiple axes.
+
+The source code of the main application is (see [`second_axis.cpp`](https://github.com/jkriege2/JKQtPlotter/tree/master/examples/second_axis/second_axis.cpp).
+
+In the code we take these step to set up a plot with two secondary axes and three graphs:
+
+
+1./2. create a plotter and create columns with different dataset:
+
+```.cpp
+    // 1. create a plotter window and get a pointer to the internal datastore (for convenience)
+    JKQTPDatastore* ds=plot.getDatastore();
+
+    // 2. now we create two columns for key and value
+    size_t columnX=ds->addLinearColumn(40, 0,10,"x");
+    size_t columnY1=ds->addColumnCalculatedFromColumn(columnX, [](double x) { return x; }, "y1");
+    size_t columnY2=ds->addColumnCalculatedFromColumn(columnX, [](double x) { return cos(x); }, "y2");
+    size_t columnY3=ds->addColumnCalculatedFromColumn(columnX, [](double x) { return x*x; }, "y3");
+```
+
+3. create a second y-axis and set its formating options, so it only draws an axis on the right
+
+```.cpp
+    auto yAxisRef2=plot.getPlotter()->addSecondaryYAxis(new JKQTPVerticalAxis(plot.getPlotter(), JKQTPPrimaryAxis));
+    plot.getYAxis(yAxisRef2)->setDrawGrid(false);
+    plot.getYAxis(yAxisRef2)->setDrawMode1(JKQTPCADMnone);
+    plot.getYAxis(yAxisRef2)->setDrawMode2(JKQTPCADMcomplete);
+    plot.getYAxis(yAxisRef2)->setDrawMode0(JKQTPCADMnone);
+    plot.getYAxis(yAxisRef2)->setShowZeroAxis(false);
+```
+
+... and ctreate third y-axis
+
+```.cpp
+    auto yAxisRef3=plot.getPlotter()->addSecondaryYAxis(new JKQTPVerticalAxis(plot.getPlotter(), JKQTPPrimaryAxis));
+    plot.getYAxis(yAxisRef3)->setDrawGrid(false);
+    plot.getYAxis(yAxisRef3)->setDrawMode1(JKQTPCADMnone);
+    plot.getYAxis(yAxisRef3)->setDrawMode2(JKQTPCADMcomplete);
+    plot.getYAxis(yAxisRef3)->setDrawMode0(JKQTPCADMnone);
+    plot.getYAxis(yAxisRef3)->setShowZeroAxis(false);
+```
+
+... reformat the major y-axis, so it does not draw on the right and thus the secondary axis yAxisRef2 replaces it there. If this step is omitted, the secondary axes stack on the right of the primary.
+
+```.cpp
+    plot.getYAxis()->setDrawMode2(JKQTPCADMnone);
+    plot.getYAxis()->setColor(graph1->getLineColor());
+```
+
+3. create graph in the plot, which plots the dataset:
+
+3.1 the first graph uses the default (primary) x/y-axes
+
+```.cpp
+    JKQTPXYLineGraph* graph1=new JKQTPXYLineGraph(&plot);
+    graph1->setKeyColumn(columnX);
+    graph1->setValueColumn(columnY1);
+    plot.addGraph(graph1);
+    plot.getYAxis()->setAxisLabel("graph1");
+```
+
+3.2 the second graph uses the default (primary) x-axis, but the secondary axis yAxisRef2 as y-axis
+
+```.cpp
+    JKQTPXYLineGraph* graph2=new JKQTPXYLineGraph(&plot);
+    graph2->setKeyColumn(columnX);
+    graph2->setValueColumn(columnY2);
+    plot.addGraph(graph2);
+```
+
+tell graph2 to use this axis
+
+```.cpp
+    graph2->setYAxis(yAxisRef2);
+```
+
+set axis color to match graph2's color
+
+```.cpp
+    plot.getYAxis(yAxisRef2)->setColor(graph2->getLineColor());
+```
+
+set axis label
+
+```.cpp
+    plot.getYAxis(yAxisRef2)->setAxisLabel("graph2");
+```
+
+3.3 the third graph uses the default (primary) x-axis, but the secondary axis yAxisRef3 as y-axis
+
+```.cpp
+    JKQTPXYLineGraph* graph3=new JKQTPXYLineGraph(&plot);
+    graph3->setKeyColumn(columnX);
+    graph3->setValueColumn(columnY3);
+    plot.addGraph(graph3);
+    plot.getYAxis(yAxisRef3)->setColor(graph3->getLineColor());
+    plot.getYAxis(yAxisRef3)->setAxisLabel("graph3");
+    graph3->setYAxis(yAxisRef3);
+
+
+```
+
+4. autoscale the plot so the graph is contained. This auto-scales all axes using the graphs (and their data) as assigned to the axes, i.e.:
+- all 3 graphs for x-axis, 
+- graph1 for primary y-axis, 
+- graph2 for secondary axis yAxisRef2
+- graph3 for secondary axis yAxisRef3
+
+```.cpp
+    plot.zoomToFit();
+```
+
+5. show plotter and make it a decent size
+
+```.cpp
+    plot.setWindowTitle(title);
+    plot.show();
+    plot.resize(500,400);
+```
+
+
+The result looks like this:
+
+![second_axis](https://raw.githubusercontent.com/jkriege2/JKQtPlotter/master/screenshots/second_axis.png)
+
+If we set seondary axes for the x-axis instead of the y-axis, i.e. use 
+```.cpp
+    // ...
+    auto xAxisRef2=plot.getPlotter()->addSecondaryXAxis(new JKQTPHorizontalAxis(plot.getPlotter(), JKQTPPrimaryAxis));
+    // ...
+```
+we get a plot like this:
+![second_axis_hor](https://raw.githubusercontent.com/jkriege2/JKQtPlotter/master/screenshots/second_axis_hor.png)
+

examples/second_axis/second_axis.cpp

@@ -0,0 +1,160 @@
+/** \example second_axis.cpp
+ * Shows how to draw Barcharts with different colors above and below the baseline in a JKQTPlotter
+ *
+ * \ref JKQTPlotterSecondaryAxes
+ */
+ 
+#include "jkqtpexampleapplication.h"
+#include <QApplication>
+#include "jkqtplotter/jkqtplotter.h"
+#include "jkqtplotter/graphs/jkqtplines.h"
+#include "jkqtpexampleapplication.h"
+
+
+
+void exampleSecondYAxis(JKQTPlotter& plot, const QString& title)
+{
+    // 1. create a plotter window and get a pointer to the internal datastore (for convenience)
+    JKQTPDatastore* ds=plot.getDatastore();
+
+    // 2. now we create two columns for key and value
+    size_t columnX=ds->addLinearColumn(40, 0,10,"x");
+    size_t columnY1=ds->addColumnCalculatedFromColumn(columnX, [](double x) { return x; }, "y1");
+    size_t columnY2=ds->addColumnCalculatedFromColumn(columnX, [](double x) { return cos(x); }, "y2");
+    size_t columnY3=ds->addColumnCalculatedFromColumn(columnX, [](double x) { return x*x; }, "y3");
+
+    // 3. create a second y-axis and set its formating options, so it only draws an axis on the right
+    auto yAxisRef2=plot.getPlotter()->addSecondaryYAxis(new JKQTPVerticalAxis(plot.getPlotter(), JKQTPPrimaryAxis));
+    plot.getYAxis(yAxisRef2)->setDrawGrid(false);
+    plot.getYAxis(yAxisRef2)->setDrawMode1(JKQTPCADMnone);
+    plot.getYAxis(yAxisRef2)->setDrawMode2(JKQTPCADMcomplete);
+    plot.getYAxis(yAxisRef2)->setDrawMode0(JKQTPCADMnone);
+    plot.getYAxis(yAxisRef2)->setShowZeroAxis(false);
+    //   ... and ctreate third y-axis
+    auto yAxisRef3=plot.getPlotter()->addSecondaryYAxis(new JKQTPVerticalAxis(plot.getPlotter(), JKQTPPrimaryAxis));
+    plot.getYAxis(yAxisRef3)->setDrawGrid(false);
+    plot.getYAxis(yAxisRef3)->setDrawMode1(JKQTPCADMnone);
+    plot.getYAxis(yAxisRef3)->setDrawMode2(JKQTPCADMcomplete);
+    plot.getYAxis(yAxisRef3)->setDrawMode0(JKQTPCADMnone);
+    plot.getYAxis(yAxisRef3)->setShowZeroAxis(false);
+    //   ... reformat the major y-axis, so it does not draw on the right and thus the secondary axis yAxisRef2 replaces it there
+    //       if this step is omitted, the secondary axes stack on the right of the primary.
+    plot.getYAxis()->setDrawMode2(JKQTPCADMnone);
+    plot.getYAxis()->setAxisLabel("graph1");
+    
+
+    // 3. create graph in the plot, which plots the dataset:
+    // 3.1 the first graph uses the default (primary) x/y-axes
+    JKQTPXYLineGraph* graph1=new JKQTPXYLineGraph(&plot);
+    graph1->setKeyColumn(columnX);
+    graph1->setValueColumn(columnY1);
+    plot.addGraph(graph1);
+    plot.getYAxis()->setColor(graph1->getLineColor());
+
+    // 3.2 the second graph uses the default (primary) x-axis, but the secondary axis yAxisRef2 as y-axis
+    JKQTPXYLineGraph* graph2=new JKQTPXYLineGraph(&plot);
+    graph2->setKeyColumn(columnX);
+    graph2->setValueColumn(columnY2);
+    plot.addGraph(graph2);
+    //    tell graph2 to use this axis
+    graph2->setYAxis(yAxisRef2);
+    //    set axis color to match graph2's color
+    plot.getYAxis(yAxisRef2)->setColor(graph2->getLineColor());
+    //    set axis label
+    plot.getYAxis(yAxisRef2)->setAxisLabel("graph2");
+
+    // 3.3 the third graph uses the default (primary) x-axis, but the secondary axis yAxisRef3 as y-axis
+    JKQTPXYLineGraph* graph3=new JKQTPXYLineGraph(&plot);
+    graph3->setKeyColumn(columnX);
+    graph3->setValueColumn(columnY3);
+    plot.addGraph(graph3);
+    plot.getYAxis(yAxisRef3)->setColor(graph3->getLineColor());
+    plot.getYAxis(yAxisRef3)->setAxisLabel("graph3");
+    graph3->setYAxis(yAxisRef3);
+
+
+    // 4. autoscale the plot so the graph is contained
+    //    This auto-scales all axes using the graphs (and their data) as assigned to the axes!
+    //    i.e. all 3 graphs for x-axis, 
+    //         graph1 for primary y-axis, 
+    //         graph2 for secondary axis yAxisRef2
+    //         graph3 for secondary axis yAxisRef3
+    plot.zoomToFit();
+
+    // 5. show plotter and make it a decent size
+    plot.setWindowTitle(title);
+    plot.show();
+    plot.resize(500,400);
+}
+
+
+
+void exampleSecondXAxis(JKQTPlotter& plot, const QString& title)
+{
+    // same as above, but with swapped x- and y-axes!!!
+    
+    JKQTPDatastore* ds=plot.getDatastore();
+
+    size_t columnY=ds->addLinearColumn(30, 0,12,"y");
+    size_t columnX1=ds->addColumnCalculatedFromColumn(columnY, [](double x) { return x; }, "x1");
+    size_t columnX2=ds->addColumnCalculatedFromColumn(columnY, [](double x) { return cos(x); }, "x2");
+    size_t columnX3=ds->addColumnCalculatedFromColumn(columnY, [](double x) { return x*x; }, "x3");
+
+    JKQTPXYLineGraph* graph1=new JKQTPXYLineGraph(&plot);
+    graph1->setXColumn(columnX1);
+    graph1->setYColumn(columnY);
+    plot.addGraph(graph1);
+    JKQTPXYLineGraph* graph2=new JKQTPXYLineGraph(&plot);
+    graph2->setXColumn(columnX2);
+    graph2->setYColumn(columnY);
+    plot.addGraph(graph2);
+    JKQTPXYLineGraph* graph3=new JKQTPXYLineGraph(&plot);
+    graph3->setXColumn(columnX3);
+    graph3->setYColumn(columnY);
+    plot.addGraph(graph3);
+
+    plot.getXAxis()->setDrawMode2(JKQTPCADMLineTicksTickLabels);
+    plot.getXAxis()->setColor(graph1->getLineColor());
+    plot.getXAxis()->setAxisLabel("graph1");
+
+    auto xAxisRef2=plot.getPlotter()->addSecondaryXAxis(new JKQTPHorizontalAxis(plot.getPlotter(), JKQTPPrimaryAxis));
+    plot.getXAxis(xAxisRef2)->setDrawGrid(false);
+    plot.getXAxis(xAxisRef2)->setDrawMode1(JKQTPCADMnone);
+    plot.getXAxis(xAxisRef2)->setDrawMode2(JKQTPCADMcomplete);
+    plot.getXAxis(xAxisRef2)->setDrawMode0(JKQTPCADMnone);
+    plot.getXAxis(xAxisRef2)->setShowZeroAxis(false);
+    plot.getXAxis(xAxisRef2)->setColor(graph2->getLineColor());
+    plot.getXAxis(xAxisRef2)->setAxisLabel("graph2");
+    graph2->setXAxis(xAxisRef2);
+
+    auto xAxisRef3=plot.getPlotter()->addSecondaryXAxis(new JKQTPHorizontalAxis(plot.getPlotter(), JKQTPPrimaryAxis));
+    plot.getXAxis(xAxisRef3)->setDrawGrid(false);
+    plot.getXAxis(xAxisRef3)->setDrawMode1(JKQTPCADMnone);
+    plot.getXAxis(xAxisRef3)->setDrawMode2(JKQTPCADMcomplete);
+    plot.getXAxis(xAxisRef3)->setDrawMode0(JKQTPCADMnone);
+    plot.getXAxis(xAxisRef3)->setShowZeroAxis(false);
+    plot.getXAxis(xAxisRef3)->setColor(graph3->getLineColor());
+    plot.getXAxis(xAxisRef3)->setAxisLabel("graph3");
+    graph3->setXAxis(xAxisRef3);
+
+    plot.zoomToFit();
+
+    plot.setWindowTitle(title);
+    plot.show();
+    plot.resize(400,500);
+}
+
+int main(int argc, char* argv[])
+{
+        
+    JKQTPAppSettingController highDPIController(argc,argv);
+    JKQTPExampleApplication app(argc, argv);
+
+
+    JKQTPlotter plotsecondY;
+    exampleSecondYAxis(plotsecondY, "1: Second Y-Axis");
+    JKQTPlotter plotsecondX;
+    exampleSecondXAxis(plotsecondX, "2: Second X-Axis");
+
+    return app.exec();
+}

lib/jkqtmath/CMakeLists.txt

@@ -115,7 +115,7 @@ if(JKQtPlotter_BUILD_STATIC_LIBS)
     write_basic_package_version_file(${CMAKE_CURRENT_BINARY_DIR}/${lib_name}Version.cmake
                                      VERSION ${PROJECT_VERSION} 
                                      COMPATIBILITY AnyNewerVersion )    
-    add_library(${oldlib_name} ALIAS ${oldlib_name})
+    add_library(${oldlib_name} ALIAS ${lib_name})
 endif()
 
 

lib/jkqtplotter/graphs/jkqtpbarchart.cpp

@@ -68,9 +68,9 @@ void JKQTPBarVerticalGraph::draw(JKQTPEnhancedPainter& painter) {
         painter.save(); auto __finalpaint=JKQTPFinally([&painter]() {painter.restore();});
 
     //    double x0=transformX(0);
-    //    if (parent->getXAxis()->isLogAxis()) x0=transformX(parent->getXAxis()->getMin());
+    //    if (getXAxis()->isLogAxis()) x0=transformX(getXAxis()->getMin());
         double y0=transformY(0);
-        if (parent->getYAxis()->isLogAxis()) y0=transformY(parent->getYAxis()->getMin());
+        if (getYAxis()->isLogAxis()) y0=transformY(getYAxis()->getMin());
         double delta=1;
         double deltap=0;
         double deltam=0;
@@ -248,9 +248,9 @@ void JKQTPBarHorizontalGraph::draw(JKQTPEnhancedPainter& painter) {
     if (getIndexRange(imin, imax)) {
 
         double x0=transformX(0);
-        if (parent->getXAxis()->isLogAxis()) x0=transformX(parent->getXAxis()->getMin());
+        if (getXAxis()->isLogAxis()) x0=transformX(getXAxis()->getMin());
     //    double y0=transformY(0);
-    //    if (parent->getYAxis()->isLogAxis()) y0=transformY(parent->getYAxis()->getMin());
+    //    if (getYAxis()->isLogAxis()) y0=transformY(getYAxis()->getMin());
         {
             painter.save(); auto __finalpaint=JKQTPFinally([&painter]() {painter.restore();});
             intSortData();

lib/jkqtplotter/graphs/jkqtpevaluatedfunction.cpp

@@ -224,12 +224,12 @@ void JKQTPEvaluatedFunctionWithErrorsGraphDrawingBase::drawXGraph(JKQTPEnhancedP
 
 
         double y0=transformY(0);
-        if (parent->getYAxis()->isLogAxis()) y0=transformY(parent->getYAxis()->getMin());
+        if (getYAxis()->isLogAxis()) y0=transformY(getYAxis()->getMin());
         bool first=false;
         QPolygonF filledPolygon, linePolygon, errorLineTop, errorLineBottom;
         QList<QPointF> epTop, epBottom;
-        double yami=qMin(transformY(parent->getYAxis()->getMin()),transformY(parent->getYAxis()->getMax()));
+        double yami=qMin(transformY(getYAxis()->getMin()),transformY(getYAxis()->getMax()));
-        double yama=qMax(transformY(parent->getYAxis()->getMin()),transformY(parent->getYAxis()->getMax()));
+        double yama=qMax(transformY(getYAxis()->getMin()),transformY(getYAxis()->getMax()));
         double dypix=fabs(yama-yami);
         yami=yami-2.0*dypix;
         yama=yama+2.0*dypix;
@@ -351,12 +351,12 @@ void JKQTPEvaluatedFunctionWithErrorsGraphDrawingBase::drawYGraph(JKQTPEnhancedP
 
 
         double x0=transformX(0);
-        if (parent->getXAxis()->isLogAxis()) x0=transformX(parent->getXAxis()->getMin());
+        if (getXAxis()->isLogAxis()) x0=transformX(getXAxis()->getMin());
         bool first=false;
         QPolygonF filledPolygon, linePolygon, errorLineTop, errorLineBottom;
         QList<QPointF> epTop, epBottom;
-        double xami=qMin(transformY(parent->getXAxis()->getMin()),transformY(parent->getXAxis()->getMax()));
+        double xami=qMin(transformY(getXAxis()->getMin()),transformY(getXAxis()->getMax()));
-        double xama=qMax(transformY(parent->getXAxis()->getMin()),transformY(parent->getXAxis()->getMax()));
+        double xama=qMax(transformY(getXAxis()->getMin()),transformY(getXAxis()->getMax()));
         double dxpix=fabs(xama-xami);
         xami=xami-2.0*dxpix;
         xama=xama+2.0*dxpix;

lib/jkqtplotter/graphs/jkqtpfilledcurve.cpp

@@ -146,10 +146,10 @@ void JKQTPFilledCurveXGraph::draw(JKQTPEnhancedPainter& painter) {
         double xold=-1;
         //double yold=-1;
         double y0=transformY(getBaseline());
-        if (parent->getYAxis()->isLogAxis()) {
+        if (getYAxis()->isLogAxis()) {
-            y0=transformY(parent->getYAxis()->getMin());
+            y0=transformY(getYAxis()->getMin());
-            if (getBaseline()>0 && getBaseline()>parent->getYAxis()->getMin()) y0=transformY(getBaseline());
+            if (getBaseline()>0 && getBaseline()>getYAxis()->getMin()) y0=transformY(getBaseline());
-            else y0=transformY(parent->getYAxis()->getMin());
+            else y0=transformY(getYAxis()->getMin());
         }
         bool subsequentItem=false;
         intSortData();
@@ -270,9 +270,9 @@ void JKQTPFilledCurveYGraph::draw(JKQTPEnhancedPainter &painter)
         //double xold=-1;
         double yold=-1;
         double x0=transformX(getBaseline());
-        if (parent->getXAxis()->isLogAxis()) {
+        if (getXAxis()->isLogAxis()) {
-            if (getBaseline()>0 && getBaseline()>parent->getXAxis()->getMin()) x0=transformX(getBaseline());
+            if (getBaseline()>0 && getBaseline()>getXAxis()->getMin()) x0=transformX(getBaseline());
-            else x0=transformX(parent->getXAxis()->getMin());
+            else x0=transformX(getXAxis()->getMin());
         }
         bool first=false;
         intSortData();

lib/jkqtplotter/graphs/jkqtpgeolines.cpp

@@ -104,7 +104,7 @@ void JKQTPGeoLine::draw(JKQTPEnhancedPainter& painter) {
     QPointF xx2(transformX(x2), transformY(y2));
     if ( QLineF(xx1, xx2).length()>0) {
 
-        if ((getDrawMode()==DrawAsGraphicElement) || (getParent()->getXAxis()->isLinearAxis() && getParent()->getYAxis()->isLinearAxis())) {
+        if ((getDrawMode()==DrawAsGraphicElement) || (getXAxis()->isLinearAxis() && getYAxis()->isLinearAxis())) {
             // for linear axes, we can simply draw a line
             const double angle1=atan2(xx2.y()-xx1.y(), xx2.x()-xx1.x());
             const double angle2=atan2(xx1.y()-xx2.y(), xx1.x()-xx2.x());
@@ -115,10 +115,10 @@ void JKQTPGeoLine::draw(JKQTPEnhancedPainter& painter) {
             painter.drawLine(QLineF(lx1, lx2));
         } else {
             QLineF line(QPointF(x1,y1), QPointF(x2,y2));
-            const double xmin=parent->getXAxis()->getMin();
+            const double xmin=getXAxis()->getMin();
-            const double xmax=parent->getXAxis()->getMax();
+            const double xmax=getXAxis()->getMax();
-            const double ymin=parent->getYAxis()->getMin();
+            const double ymin=getYAxis()->getMin();
-            const double ymax=parent->getYAxis()->getMax();
+            const double ymax=getYAxis()->getMax();
             const QRectF bbox(QPointF(xmin, ymin), QPointF(xmax, ymax));
             bool drawHead=bbox.contains(line.p2());
             bool drawTail=bbox.contains(line.p1());
@@ -283,10 +283,10 @@ void JKQTPGeoInfiniteLine::draw(JKQTPEnhancedPainter& painter) {
     clearHitTestData();
     reserveHitTestData(2);
 
-    double xmin=parent->getXAxis()->getMin();
+    double xmin=getXAxis()->getMin();
-    double xmax=parent->getXAxis()->getMax();
+    double xmax=getXAxis()->getMax();
-    double ymin=parent->getYAxis()->getMin();
+    double ymin=getYAxis()->getMin();
-    double ymax=parent->getYAxis()->getMax();
+    double ymax=getYAxis()->getMax();
     QRectF bbox(QPointF(xmin, ymin), QPointF(xmax, ymax));
     bool doDraw=false;
     double x2=x, y2=y;
@@ -404,7 +404,7 @@ void JKQTPGeoInfiniteLine::draw(JKQTPEnhancedPainter& painter) {
         if (line.length()>0) {
             QPointF xx1;
             double angle1=0;
-            if ((getDrawMode()==DrawAsGraphicElement) || (getParent()->getXAxis()->isLinearAxis() && getParent()->getYAxis()->isLinearAxis())) {
+            if ((getDrawMode()==DrawAsGraphicElement) || (getXAxis()->isLinearAxis() && getYAxis()->isLinearAxis())) {
                 painter.drawLine(line);
                 xx1=QPointF(transformX(x),transformY(y));
                 angle1=atan2(line.dy(), line.dx());
@@ -579,7 +579,7 @@ void JKQTPGeoPolyLines::draw(JKQTPEnhancedPainter& painter) {
         painter.save(); auto __finalpaint=JKQTPFinally([&painter]() {painter.restore();});
         painter.setPen(getLinePen(painter, parent));
         painter.setBrush(getLineColor());
-        if ((getDrawMode()==DrawAsGraphicElement) || (getParent()->getXAxis()->isLinearAxis() && getParent()->getYAxis()->isLinearAxis())) {
+        if ((getDrawMode()==DrawAsGraphicElement) || (getXAxis()->isLinearAxis() && getYAxis()->isLinearAxis())) {
             QVector<QPointF> path=transform(points);
             angle1=atan2(path[1].y()-path[0].y(), path[1].x()-path[0].x());
             angle2=atan2(path[path.size()-2].y()-path[path.size()-1].y(), path[path.size()-2].x()-path[path.size()-1].x());

lib/jkqtplotter/graphs/jkqtpgeoshapes.cpp

@@ -132,7 +132,7 @@ void JKQTPGeoRectangle::draw(JKQTPEnhancedPainter& painter) {
     QPolygonF poly=getPolygon();
     reserveHitTestData(poly.size());
     QPolygonF rect;
-    if ((getDrawMode()==DrawAsGraphicElement) || (getParent()->getXAxis()->isLinearAxis() && getParent()->getYAxis()->isLinearAxis())) {
+    if ((getDrawMode()==DrawAsGraphicElement) || (getXAxis()->isLinearAxis() && getYAxis()->isLinearAxis())) {
         rect=transform(poly);
     } else {
         auto fTransform=std::bind([](const JKQTPGeometricPlotElement* plot, const QPointF& p) { return plot->transform(p); }, this, std::placeholders::_1);
@@ -313,7 +313,7 @@ void JKQTPGeoPolygon::draw(JKQTPEnhancedPainter& painter) {
         painter.save(); auto __finalpaint=JKQTPFinally([&painter]() {painter.restore();});
         painter.setPen(getLinePen(painter, parent));
         painter.setBrush(getFillBrush(painter, parent));
-        if ((getDrawMode()==DrawAsGraphicElement) || (getParent()->getXAxis()->isLinearAxis() && getParent()->getYAxis()->isLinearAxis())) {
+        if ((getDrawMode()==DrawAsGraphicElement) || (getXAxis()->isLinearAxis() && getYAxis()->isLinearAxis())) {
             painter.drawPolygon(transform(points));
         } else {
             // for non-linear axes, a line might not be drawn as a line, so we need to segment the line (i.e. linear function in coordinate space)

lib/jkqtplotter/graphs/jkqtpimpulses.cpp

@@ -206,9 +206,9 @@ void JKQTPImpulsesHorizontalGraph::draw(JKQTPEnhancedPainter& painter) {
         if (getIndexRange(imin, imax)) {
 
             double x0=transformX(getBaseline());
-            if (parent->getXAxis()->isLogAxis()) {
+            if (getXAxis()->isLogAxis()) {
-                if (getBaseline()>0 && getBaseline()>parent->getXAxis()->getMin()) x0=transformX(getBaseline());
+                if (getBaseline()>0 && getBaseline()>getXAxis()->getMin()) x0=transformX(getBaseline());
-                else x0=transformX(parent->getXAxis()->getMin());
+                else x0=transformX(getXAxis()->getMin());
             }
 
             QVector<QLineF> lines;
@@ -364,9 +364,9 @@ void JKQTPImpulsesVerticalGraph::draw(JKQTPEnhancedPainter& painter) {
 
 
             double y0=transformY(getBaseline());
-            if (parent->getYAxis()->isLogAxis()) {
+            if (getYAxis()->isLogAxis()) {
-                if (getBaseline()>0 && getBaseline()>parent->getYAxis()->getMin()) y0=transformY(getBaseline());
+                if (getBaseline()>0 && getBaseline()>getYAxis()->getMin()) y0=transformY(getBaseline());
-                else y0=transformY(parent->getYAxis()->getMin());
+                else y0=transformY(getYAxis()->getMin());
             }
             QVector<QLineF> lines;
             QVector<QPointF> points;

lib/jkqtplotter/graphs/jkqtplines.cpp

@@ -78,10 +78,10 @@ void JKQTPXYLineGraph::draw(JKQTPEnhancedPainter& painter) {
         const QPen p=getLinePen(painter, parent);
         const QPen penSelection=getHighlightingLinePen(painter, parent);
         const auto symType=getSymbolType();
-        const double xmin=transformX(parent->getXAxis()->getMin());
+        const double xmin=transformX(getXAxis()->getMin());
-        const double xmax=transformX(parent->getXAxis()->getMax());
+        const double xmax=transformX(getXAxis()->getMax());
-        const double ymin=transformY(parent->getYAxis()->getMin());
+        const double ymin=transformY(getYAxis()->getMin());
-        const double ymax=transformY(parent->getYAxis()->getMax());
+        const double ymax=transformY(getYAxis()->getMax());
         const double symbolSize=parent->pt2px(painter, getSymbolSize());
         const QMarginsF clipMargins=(symType==JKQTPNoSymbol)?QMarginsF(0,0,0,0):QMarginsF(symbolSize,symbolSize,symbolSize,symbolSize);
         const QRectF cliprect=QRectF(qMin(xmin,xmax),qMin(ymin,ymax),fabs(xmax-xmin),fabs(ymax-ymin))+clipMargins;
@@ -108,7 +108,7 @@ void JKQTPXYLineGraph::draw(JKQTPEnhancedPainter& painter) {
                     //if (isHighlighted() && getSymbolType()!=JKQTPNoSymbol) {
                         //JKQTPPlotSymbol(painter, x, y, JKQTPFilledCircle, parent->pt2px(painter, symbolSize*1.5), parent->pt2px(painter, symbolWidth*parent->getLineWidthMultiplier()), penSelection.color(), penSelection.color(),getSymbolFont());
                     //}
-                    if ((!parent->getXAxis()->isLogAxis() || xv>0.0) && (!parent->getYAxis()->isLogAxis() || yv>0.0) ) {
+                    if ((!getXAxis()->isLogAxis() || xv>0.0) && (!getYAxis()->isLogAxis() || yv>0.0) ) {
                         if (symType!=JKQTPNoSymbol && cliprect.contains(x,y)) {
                             if (drawLineInForeground) plotStyledSymbol(parent, painter, x, y);
                             else symbols.push_back({x,y});

lib/jkqtplotter/graphs/jkqtprange.cpp

@@ -255,10 +255,10 @@ void JKQTPHorizontalRange::draw(JKQTPEnhancedPainter& painter) {
     double c=transformY(rangeCenter);
     double cmi=transformY(rangeMin);
     double cma=transformY(rangeMax);
-    double smi=transformY(parent->getYAxis()->getMin());
+    double smi=transformY(getYAxis()->getMin());
-    double sma=transformY(parent->getYAxis()->getMax());
+    double sma=transformY(getYAxis()->getMax());
-    double mi=transformX(parent->getXAxis()->getMin());
+    double mi=transformX(getXAxis()->getMin());
-    double ma=transformX(parent->getXAxis()->getMax());
+    double ma=transformX(getXAxis()->getMax());
     if (!unlimitedSizeMin) mi=transformX(sizeMin);
     if (!unlimitedSizeMax) ma=transformX(sizeMax);
     //std::cout<<"hor: rangeMin="<<rangeMin<<" -> "<<cmi<<std::endl;
@@ -380,10 +380,10 @@ void JKQTPVerticalRange::draw(JKQTPEnhancedPainter& painter) {
     double c=transformX(rangeCenter);
     double cmi=transformX(rangeMin);
     double cma=transformX(rangeMax);
-    double mi=transformY(parent->getYAxis()->getMin());
+    double mi=transformY(getYAxis()->getMin());
-    double ma=transformY(parent->getYAxis()->getMax());
+    double ma=transformY(getYAxis()->getMax());
-    double smi=transformX(parent->getXAxis()->getMin());
+    double smi=transformX(getXAxis()->getMin());
-    double sma=transformX(parent->getXAxis()->getMax());
+    double sma=transformX(getXAxis()->getMax());
     if (!unlimitedSizeMin) mi=transformY(sizeMin);
     if (!unlimitedSizeMax) ma=transformY(sizeMax);
     painter.save(); auto __finalpaint=JKQTPFinally([&painter]() {painter.restore();});

lib/jkqtplotter/graphs/jkqtpscatter.cpp

@@ -78,10 +78,10 @@ void JKQTPXYScatterGraph::draw(JKQTPEnhancedPainter& painter) {
         //qDebug()<<"JKQTPXYScatterGraph::draw(): "<<2;
 
         const auto symType=getSymbolType();
-        const double xmin=transformX(parent->getXAxis()->getMin());
+        const double xmin=transformX(getXAxis()->getMin());
-        const double xmax=transformX(parent->getXAxis()->getMax());
+        const double xmax=transformX(getXAxis()->getMax());
-        const double ymin=transformY(parent->getYAxis()->getMin());
+        const double ymin=transformY(getYAxis()->getMin());
-        const double ymax=transformY(parent->getYAxis()->getMax());
+        const double ymax=transformY(getYAxis()->getMax());
         const double symbolSize=parent->pt2px(painter, getSymbolSize());
         const QMarginsF clipMargins=(symType==JKQTPNoSymbol)?QMarginsF(0,0,0,0):QMarginsF(symbolSize,symbolSize,symbolSize,symbolSize);
         const QRectF cliprect=QRectF(qMin(xmin,xmax),qMin(ymin,ymax),fabs(xmax-xmin),fabs(ymax-ymin))+clipMargins;
@@ -102,7 +102,7 @@ void JKQTPXYScatterGraph::draw(JKQTPEnhancedPainter& painter) {
                     //if (isHighlighted() && getSymbolType()!=JKQTPNoSymbol) {
                         //JKQTPPlotSymbol(painter, x, y, JKQTPFilledCircle, parent->pt2px(painter, symbolSize*1.5), parent->pt2px(painter, symbolWidth*parent->getLineWidthMultiplier()), penSelection.color(), penSelection.color());
                     //}
-                    if ((!parent->getXAxis()->isLogAxis() || xv>0.0) && (!parent->getYAxis()->isLogAxis() || yv>0.0) ) {
+                    if ((!getXAxis()->isLogAxis() || xv>0.0) && (!getYAxis()->isLogAxis() || yv>0.0) ) {
                         if (symType!=JKQTPNoSymbol && cliprect.contains(x,y)) plotStyledSymbol(parent, painter, x, y);
                     }
                 }
@@ -364,7 +364,7 @@ void JKQTPXYParametrizedScatterGraph::draw(JKQTPEnhancedPainter &painter)
                         linewidths<<lineW;
                     }
 
-                    if ((!parent->getXAxis()->isLogAxis() || xv>0.0) && (!parent->getYAxis()->isLogAxis() || yv>0.0) ) {
+                    if ((!getXAxis()->isLogAxis() || xv>0.0) && (!getYAxis()->isLogAxis() || yv>0.0) ) {
                         if (isHighlighted() && getSymbolType()!=JKQTPNoSymbol && symbolColumn<0) {
                             JKQTPPlotSymbol(painter, x, y, JKQTPFilledCircle,symbSize*1.25, parent->pt2px(painter, getSymbolLineWidth()*parent->getLineWidthMultiplier()), penSelection.color(), penSelection.color(),getSymbolFont());
                         } else {

lib/jkqtplotter/graphs/jkqtpspecialline.cpp

@@ -128,10 +128,10 @@ void JKQTPSpecialLineHorizontalGraph::draw(JKQTPEnhancedPainter& painter) {
     QPen ph=getHighlightingLinePen(painter, parent);
     QPen np(Qt::NoPen);
     QBrush b=getFillBrush(painter, parent);
-    const double xmin=transformX(parent->getXAxis()->getMin());
+    const double xmin=transformX(getXAxis()->getMin());
-    const double xmax=transformX(parent->getXAxis()->getMax());
+    const double xmax=transformX(getXAxis()->getMax());
-    const double ymin=transformY(parent->getYAxis()->getMin());
+    const double ymin=transformY(getYAxis()->getMin());
-    const double ymax=transformY(parent->getYAxis()->getMax());
+    const double ymax=transformY(getYAxis()->getMax());
     const auto symType=getSymbolType();
     const double symbolSize=parent->pt2px(painter, getSymbolSize());
     const QMarginsF clipMargins=(symType==JKQTPNoSymbol)?QMarginsF(0,0,0,0):QMarginsF(symbolSize,symbolSize,symbolSize,symbolSize);
@@ -149,9 +149,9 @@ void JKQTPSpecialLineHorizontalGraph::draw(JKQTPEnhancedPainter& painter) {
         double xold=-1;
         double yold=-1;
         double y0=transformY(getBaseline());
-        if (parent->getYAxis()->isLogAxis()) {
+        if (getYAxis()->isLogAxis()) {
-            if (getBaseline()>0 && getBaseline()>parent->getYAxis()->getMin()) y0=transformY(getBaseline());
+            if (getBaseline()>0 && getBaseline()>getYAxis()->getMin()) y0=transformY(getBaseline());
-            else y0=transformY(parent->getYAxis()->getMin());
+            else y0=transformY(getYAxis()->getMin());
         }
         bool firstPoint=true;
         intSortData();
@@ -336,10 +336,10 @@ void JKQTPSpecialLineVerticalGraph::draw(JKQTPEnhancedPainter& painter) {
     QPen ph=getHighlightingLinePen(painter, parent);
     QPen np(Qt::NoPen);
     QBrush b=getFillBrush(painter, parent);
-    const double xmin=transformX(parent->getXAxis()->getMin());
+    const double xmin=transformX(getXAxis()->getMin());
-    const double xmax=transformX(parent->getXAxis()->getMax());
+    const double xmax=transformX(getXAxis()->getMax());
-    const double ymin=transformY(parent->getYAxis()->getMin());
+    const double ymin=transformY(getYAxis()->getMin());
-    const double ymax=transformY(parent->getYAxis()->getMax());
+    const double ymax=transformY(getYAxis()->getMax());
     const auto symType=getSymbolType();
     const double symbolSize=parent->pt2px(painter, getSymbolSize());
     const QMarginsF clipMargins=(symType==JKQTPNoSymbol)?QMarginsF(0,0,0,0):QMarginsF(symbolSize,symbolSize,symbolSize,symbolSize);
@@ -357,9 +357,9 @@ void JKQTPSpecialLineVerticalGraph::draw(JKQTPEnhancedPainter& painter) {
         double xold=-1;
         double yold=-1;
         double x0=transformX(getBaseline());
-        if (parent->getXAxis()->isLogAxis()) {
+        if (getXAxis()->isLogAxis()) {
-            if (getBaseline()>0 && getBaseline()>parent->getXAxis()->getMin()) x0=transformX(getBaseline());
+            if (getBaseline()>0 && getBaseline()>getXAxis()->getMin()) x0=transformX(getBaseline());
-            else x0=transformX(parent->getXAxis()->getMin());
+            else x0=transformX(getXAxis()->getMin());
         }
         bool first=false;
         intSortData();

lib/jkqtplotter/jkqtpbaseplotter.cpp

@@ -48,16 +48,10 @@
 #ifdef QFWIDLIB_LIBRARY
 #  include "qftools.h"
 #endif
-#include "jkqtplotter/graphs/jkqtpboxplot.h"
-#include "jkqtplotter/graphs/jkqtpbarchart.h"
-#include "jkqtplotter/graphs/jkqtpfilledcurve.h"
-#include "jkqtplotter/graphs/jkqtpspecialline.h"
-#include "jkqtplotter/graphs/jkqtpimpulses.h"
-#include "jkqtplotter/graphs/jkqtpscatter.h"
-#include "jkqtplotter/graphs/jkqtpgeometric.h"
 #include "jkqtplotter/graphs/jkqtpimage.h"
 #include "jkqtplotter/graphs/jkqtpimagergb.h"
 #include "jkqtmathtext/jkqtmathtext.h"
+#include <algorithm>
 
 static QString globalUserSettigsFilename="";
 static QString globalUserSettigsPrefix="";
@@ -302,6 +296,15 @@ JKQTBasePlotter::~JKQTBasePlotter(){
     if (datastoreInternal && datastore!=nullptr) delete datastore;
     delete xAxis;
     delete yAxis;
+    for (const auto& ax: qAsConst(secondaryYAxis)) {
+        delete ax;
+    }
+    secondaryYAxis.clear();
+    for (const auto& ax: qAsConst(secondaryXAxis)) {
+        delete ax;
+    }
+    secondaryXAxis.clear();
+
 }
 
 void JKQTBasePlotter::setGrid(bool val) {
@@ -345,8 +348,8 @@ void JKQTBasePlotter::setMinorGridStyle(Qt::PenStyle __value)
 }
 
 void JKQTBasePlotter::setShowZeroAxes(bool showX, bool showY) {
-    getXAxis()->setShowZeroAxis(showX);
+    xAxis->setShowZeroAxis(showX);
-    getYAxis()->setShowZeroAxis(showY);
+    yAxis->setShowZeroAxis(showY);
 }
 
 void JKQTBasePlotter::setShowZeroAxes(bool showXY) {
@@ -410,10 +413,10 @@ void JKQTBasePlotter::initSettings() {
     gridPrintingCurrentY=0;
 
 
-    internalPlotBorderLeft_notIncludingOutsidePlotSections=internalPlotBorderLeft=plotterStyle.plotBorderLeft;
+    internalPlotBorderLeft_notIncludingAxisAndOutsidePlotSections=internalPlotBorderLeft_notIncludingOutsidePlotSections=internalPlotBorderLeft=plotterStyle.plotBorderLeft;
-    internalPlotBorderRight_notIncludingOutsidePlotSections=internalPlotBorderRight=plotterStyle.plotBorderRight;
+    internalPlotBorderRight_notIncludingAxisAndOutsidePlotSections=internalPlotBorderRight_notIncludingOutsidePlotSections=internalPlotBorderRight=plotterStyle.plotBorderRight;
-    internalPlotBorderTop_notIncludingOutsidePlotSections=internalPlotBorderTop=plotterStyle.plotBorderTop;
+    internalPlotBorderTop_notIncludingAxisAndOutsidePlotSections=internalPlotBorderTop_notIncludingOutsidePlotSections=internalPlotBorderTop=plotterStyle.plotBorderTop;
-    internalPlotBorderBottom_notIncludingOutsidePlotSections=internalPlotBorderBottom=plotterStyle.plotBorderBottom;
+    internalPlotBorderBottom_notIncludingAxisAndOutsidePlotSections=internalPlotBorderBottom_notIncludingOutsidePlotSections=internalPlotBorderBottom=plotterStyle.plotBorderBottom;
 
     //plotWidth=700;
     //plotHeight=150;
@@ -434,14 +437,18 @@ void JKQTBasePlotter::initSettings() {
 
 void JKQTBasePlotter::zoomIn(double factor) {
     //std::cout<<(double)event->delta()/120.0<<":   "<<factor<<std::endl;
-    double xmin=p2x(static_cast<long>(round(static_cast<double>(internalPlotWidth)/2.0-static_cast<double>(internalPlotWidth)/(2.0*factor))));
-    double xmax=p2x(static_cast<long>(round(static_cast<double>(internalPlotWidth)/2.0+static_cast<double>(internalPlotWidth)/(2.0*factor))));
-    double ymin=p2y(static_cast<long>(round(static_cast<double>(internalPlotHeight)/2.0+static_cast<double>(internalPlotHeight)/(2.0*factor))));
-    double ymax=p2y(static_cast<long>(round(static_cast<double>(internalPlotHeight)/2.0-static_cast<double>(internalPlotHeight)/(2.0*factor))));
 
+    for (auto ax: getXAxes(true)) {
+        const double xmin=ax->p2x(static_cast<long>(round(static_cast<double>(internalPlotWidth)/2.0-static_cast<double>(internalPlotWidth)/(2.0*factor))));
+        const double xmax=ax->p2x(static_cast<long>(round(static_cast<double>(internalPlotWidth)/2.0+static_cast<double>(internalPlotWidth)/(2.0*factor))));
+        ax->setRange(xmin, xmax);
+    }
+    for (auto ax: getYAxes(true)) {
+        const double ymin=ax->p2x(static_cast<long>(round(static_cast<double>(internalPlotHeight)/2.0+static_cast<double>(internalPlotHeight)/(2.0*factor))));
+        const double ymax=ax->p2x(static_cast<long>(round(static_cast<double>(internalPlotHeight)/2.0-static_cast<double>(internalPlotHeight)/(2.0*factor))));
+        ax->setRange(ymin, ymax);
+    }
 
-    xAxis->setRange(xmin, xmax);
-    yAxis->setRange(ymin, ymax);
     if (emitPlotSignals) emit plotUpdated();
     if (emitSignals) emit zoomChangedLocally(xAxis->getMin(), xAxis->getMax(), yAxis->getMin(), yAxis->getMax(), this);
 }
@@ -721,22 +728,36 @@ void JKQTBasePlotter::correctXYRangeForAspectRatio(double& xminn, double& xmaxx,
 }
 
 
-void JKQTBasePlotter::setXY(double xminn, double xmaxx, double yminn, double ymaxx) {
+void JKQTBasePlotter::setXY(double xminn, double xmaxx, double yminn, double ymaxx, bool affectsSecondaryAxes) {
 
     correctXYRangeForAspectRatio(xminn, xmaxx, yminn, ymaxx);
 
+    const double xminpix=xAxis->x2p(xminn);
+    const double xmaxpix=xAxis->x2p(xmaxx);
+    const double yminpix=yAxis->x2p(yminn);
+    const double ymaxpix=yAxis->x2p(ymaxx);
+
     xAxis->setRange(xminn, xmaxx);
     yAxis->setRange(yminn, ymaxx);
 
+    if (affectsSecondaryAxes) {
+        for (auto ax: getXAxes(false)) {
+            ax->setRange(ax->p2x(xminpix), ax->p2x(xmaxpix));
+        }
+        for (auto ax: getYAxes(false)) {
+            ax->setRange(ax->p2x(yminpix), ax->p2x(ymaxpix));
+        }
+    }
+
     if (emitSignals) emit zoomChangedLocally(xAxis->getMin(), xAxis->getMax(), yAxis->getMin(), yAxis->getMax(), this);
 }
 
-void JKQTBasePlotter::setX(double xminn, double xmaxx){
+void JKQTBasePlotter::setX(double xminn, double xmaxx, bool affectsSecondaryAxes){
-    setXY(xminn, xmaxx, yAxis->getMin(), yAxis->getMax());
+    setXY(xminn, xmaxx, yAxis->getMin(), yAxis->getMax(), affectsSecondaryAxes);
 }
 
-void JKQTBasePlotter::setY(double yminn, double ymaxx) {
+void JKQTBasePlotter::setY(double yminn, double ymaxx, bool affectsSecondaryAxes) {
-    setXY(xAxis->getMin(), xAxis->getMax(), yminn, ymaxx);
+    setXY(xAxis->getMin(), xAxis->getMax(), yminn, ymaxx, affectsSecondaryAxes);
 }
 
 void JKQTBasePlotter::setAbsoluteX(double xminn, double xmaxx) {
@@ -820,7 +841,7 @@ void JKQTBasePlotter::calcPlotScaling(JKQTPEnhancedPainter& painter){
 
     /*if (displayMousePosition) {
         QFontMetrics fm=fontMetrics();
-        QString test="<EFBFBD>Aquator";
+        QString test="Aquator";
         int labelHeight=fm.size(Qt::TextSingleLine, test).height()*1.5;
         //if (mousePosLabel!=nullptr) labelHeight=mousePosLabel->height();
         internalPlotBorderTop=internalPlotBorderTop+(labelHeight-plotBorderTop)*1.1;
@@ -837,15 +858,27 @@ void JKQTBasePlotter::calcPlotScaling(JKQTPEnhancedPainter& painter){
     s=yAxis->getSize2(painter);
     internalPlotBorderRight+=s.width();
 
+    internalPlotBorderTop_notIncludingAxisAndOutsidePlotSections=internalPlotBorderTop;
+    internalPlotBorderLeft_notIncludingAxisAndOutsidePlotSections=internalPlotBorderLeft;
+    internalPlotBorderBottom_notIncludingAxisAndOutsidePlotSections=internalPlotBorderBottom;
+    internalPlotBorderRight_notIncludingAxisAndOutsidePlotSections=internalPlotBorderRight;
+
+
+    // read size required by secondary axes
+    for (const auto& ax: qAsConst(secondaryYAxis)) {
+        internalPlotBorderLeft+=ax->getSize1(painter).width()+plotterStyle.secondaryAxisSeparation;
+        internalPlotBorderRight+=ax->getSize2(painter).width()+plotterStyle.secondaryAxisSeparation;
+    }
+    for (const auto& ax: qAsConst(secondaryXAxis)) {
+        internalPlotBorderBottom+=ax->getSize1(painter).height()+plotterStyle.secondaryAxisSeparation;
+        internalPlotBorderTop+=ax->getSize2(painter).height()+plotterStyle.secondaryAxisSeparation;
+    }
+
     internalPlotBorderTop_notIncludingOutsidePlotSections=internalPlotBorderTop;
     internalPlotBorderLeft_notIncludingOutsidePlotSections=internalPlotBorderLeft;
     internalPlotBorderBottom_notIncludingOutsidePlotSections=internalPlotBorderBottom;
     internalPlotBorderRight_notIncludingOutsidePlotSections=internalPlotBorderRight;
 
-
-
-
-
     // read additional space required by graphs
     for (int i=0; i<graphs.size(); i++) {
         if (graphs[i]->isVisible()) {
@@ -925,8 +958,9 @@ void JKQTBasePlotter::calcPlotScaling(JKQTPEnhancedPainter& painter){
     }
 
 
-    xAxis->calcPlotScaling(true);
+    for (auto ax: getAxes(true)) {
-    yAxis->calcPlotScaling(true);
+        ax->calcPlotScaling(true);
+    }
 
     ////////////////////////////////////////////////////////////////////
     // ENSURE ASPECT RATIO OF PLOT 1x1 PIXELS (if activated)
@@ -948,8 +982,9 @@ void JKQTBasePlotter::calcPlotScaling(JKQTPEnhancedPainter& painter){
         }
         xAxis->setRange(xmid-newPlotWidth/2.0, xmid+newPlotWidth/2.0);
         yAxis->setRange(ymid-newPlotHeight/2.0, ymid+newPlotHeight/2.0);
-        xAxis->calcPlotScaling(true);
+        for (auto ax: getAxes(true)) {
-        yAxis->calcPlotScaling(true);
+            ax->calcPlotScaling(true);
+        }
     }
 
 
@@ -963,8 +998,10 @@ void JKQTBasePlotter::drawSystemGrid(JKQTPEnhancedPainter& painter) {
     JKQTPAutoOutputTimer jkaaot("JKQTBasePlotter::drawSystemGrid");
 #endif
     //qDebug()<<"start JKQTBasePlotter::drawSystemGrid";
-    xAxis->drawGrids(painter);
+    for (auto ax: getAxes(true)) {
-    yAxis->drawGrids(painter);
+        ax->drawGrids(painter);
+    }
+
     //qDebug()<<"  end JKQTBasePlotter::drawSystemGrid";
 }
 
@@ -975,6 +1012,21 @@ void JKQTBasePlotter::drawSystemXAxis(JKQTPEnhancedPainter& painter) {
     //qDebug()<<"start JKQTBasePlotter::drawSystemXAxis";    
     xAxis->drawAxes(painter);
     //qDebug()<<"  end JKQTBasePlotter::drawSystemXAxis";
+
+    if (secondaryXAxis.size()>0) {
+        double ibMove1=xAxis->getSize1(painter).height();
+        if (ibMove1>0) ibMove1+=plotterStyle.secondaryAxisSeparation;
+        double ibMove2=xAxis->getSize2(painter).height();
+        if (ibMove2>0) ibMove1+=plotterStyle.secondaryAxisSeparation;
+
+        for (auto& ax: secondaryXAxis) {
+            ax->drawAxes(painter, ibMove1, ibMove2);
+            const double add1=ax->getSize1(painter).height();
+            const double add2=ax->getSize2(painter).height();
+            if (add1>0) ibMove1+=add1+plotterStyle.secondaryAxisSeparation;
+            if (add2>0) ibMove2+=add2+plotterStyle.secondaryAxisSeparation;
+        }
+    }
 }
 
 void JKQTBasePlotter::drawSystemYAxis(JKQTPEnhancedPainter& painter) {
@@ -984,6 +1036,21 @@ void JKQTBasePlotter::drawSystemYAxis(JKQTPEnhancedPainter& painter) {
     //qDebug()<<"start JKQTBasePlotter::drawSystemYAxis";
     yAxis->drawAxes(painter);
     //qDebug()<<"  end JKQTBasePlotter::drawSystemYAxis";
+
+    if (secondaryYAxis.size()>0) {
+        double ibMove1=yAxis->getSize1(painter).width();
+        if (ibMove1>0) ibMove1+=plotterStyle.secondaryAxisSeparation;
+        double ibMove2=yAxis->getSize2(painter).width();
+        if (ibMove2>0) ibMove1+=plotterStyle.secondaryAxisSeparation;
+
+        for (auto& ax: secondaryYAxis) {
+            ax->drawAxes(painter, ibMove1, ibMove2);
+            const double add1=ax->getSize1(painter).width();
+            const double add2=ax->getSize2(painter).width();
+            if (add1>0) ibMove1+=add1+plotterStyle.secondaryAxisSeparation;
+            if (add2>0) ibMove2+=add2+plotterStyle.secondaryAxisSeparation;
+        }
+    }
 }
 
 
@@ -1332,6 +1399,12 @@ void JKQTBasePlotter::drawPlot(JKQTPEnhancedPainter& painter) {
         p.setStyle(Qt::DotLine);
         painter.setPen(p);
         painter.drawRect(QRectF(internalPlotBorderLeft_notIncludingOutsidePlotSections, internalPlotBorderTop_notIncludingOutsidePlotSections, widgetWidth-internalPlotBorderLeft_notIncludingOutsidePlotSections-internalPlotBorderRight_notIncludingOutsidePlotSections, widgetHeight-internalPlotBorderTop_notIncludingOutsidePlotSections-internalPlotBorderBottom_notIncludingOutsidePlotSections));
+        p.setColor(QColor("goldenrod"));
+        col=p.color(); col.setAlphaF(0.8f); p.setColor(col);
+        p.setWidthF(plotterStyle.debugRegionLineWidth);
+        p.setStyle(Qt::DotLine);
+        painter.setPen(p);
+        painter.drawRect(QRectF(internalPlotBorderLeft_notIncludingAxisAndOutsidePlotSections, internalPlotBorderTop_notIncludingAxisAndOutsidePlotSections, widgetWidth-internalPlotBorderLeft_notIncludingAxisAndOutsidePlotSections-internalPlotBorderRight_notIncludingAxisAndOutsidePlotSections, widgetHeight-internalPlotBorderTop_notIncludingAxisAndOutsidePlotSections-internalPlotBorderBottom_notIncludingAxisAndOutsidePlotSections));
         p.setColor(QColor("yellow"));
         col=p.color(); col.setAlphaF(0.8f); p.setColor(col);
         p.setWidthF(plotterStyle.debugRegionLineWidth);
@@ -2439,6 +2512,11 @@ void JKQTBasePlotter::drawNonGrid(JKQTPEnhancedPainter& painter, const QPoint& p
     emitPlotSignals=oldEmitPlotSignals;
 }
 
+void JKQTBasePlotter::updateSecondaryAxes()
+{
+
+}
+
 void JKQTBasePlotter::setEmittingPlotSignalsEnabled(bool __value)
 {
     this->emitPlotSignals = __value;
@@ -3227,20 +3305,95 @@ const JKQTMathText *JKQTBasePlotter::getMathText() const {
     return &mathText;
 }
 
-JKQTPHorizontalAxis *JKQTBasePlotter::getXAxis() {
+JKQTPHorizontalAxisBase *JKQTBasePlotter::getXAxis(JKQTPCoordinateAxisRef axis) {
-    return xAxis;
+    if (axis==JKQTPPrimaryAxis) return xAxis;
+    else return secondaryXAxis[axis];
 }
 
-JKQTPVerticalAxis *JKQTBasePlotter::getYAxis() {
+JKQTPVerticalAxisBase *JKQTBasePlotter::getYAxis(JKQTPCoordinateAxisRef axis) {
-    return yAxis;
+    if (axis==JKQTPPrimaryAxis) return yAxis;
+    else return secondaryYAxis[axis];
 }
 
-const JKQTPHorizontalAxis *JKQTBasePlotter::getXAxis() const {
+const JKQTPHorizontalAxisBase *JKQTBasePlotter::getXAxis(JKQTPCoordinateAxisRef axis) const {
-    return xAxis;
+    if (axis==JKQTPPrimaryAxis) return xAxis;
+    else return secondaryXAxis[axis];
 }
 
-const JKQTPVerticalAxis *JKQTBasePlotter::getYAxis() const {
+const JKQTPVerticalAxisBase *JKQTBasePlotter::getYAxis(JKQTPCoordinateAxisRef axis) const {
-    return yAxis;
+    if (axis==JKQTPPrimaryAxis) return yAxis;
+    else return secondaryYAxis[axis];
+}
+
+bool JKQTBasePlotter::hasXAxis(JKQTPCoordinateAxisRef axis) const
+{
+    return secondaryXAxis.contains(axis);
+}
+
+bool JKQTBasePlotter::hasYAxis(JKQTPCoordinateAxisRef axis) const
+{
+    return secondaryYAxis.contains(axis);
+}
+
+QSet<JKQTPCoordinateAxisRef> JKQTBasePlotter::getAvailableXAxisRefs(bool includePrimary) const
+{
+    QSet<JKQTPCoordinateAxisRef> res(secondaryXAxis.keyBegin(),secondaryXAxis.keyEnd());
+    if (includePrimary) res.insert(JKQTPPrimaryAxis);
+        return res;
+}
+
+QSet<JKQTPCoordinateAxisRef> JKQTBasePlotter::getAvailableYAxisRefs(bool includePrimary) const
+{
+    QSet<JKQTPCoordinateAxisRef> res(secondaryYAxis.keyBegin(),secondaryYAxis.keyEnd());
+    if (includePrimary) res.insert(JKQTPPrimaryAxis);
+    return res;
+}
+
+QMap<JKQTPCoordinateAxisRef, JKQTPHorizontalAxisBase *> JKQTBasePlotter::getXAxes(bool includePrimary)
+{
+    QMap<JKQTPCoordinateAxisRef, JKQTPHorizontalAxisBase *> res=secondaryXAxis;
+    if (includePrimary) res[JKQTPPrimaryAxis]=xAxis;
+    return res;
+}
+
+QMap<JKQTPCoordinateAxisRef, JKQTPVerticalAxisBase *> JKQTBasePlotter::getYAxes(bool includePrimary)
+{
+    QMap<JKQTPCoordinateAxisRef, JKQTPVerticalAxisBase *> res=secondaryYAxis;
+    if (includePrimary) res[JKQTPPrimaryAxis]=yAxis;
+    return res;
+}
+
+QList<JKQTPCoordinateAxis *> JKQTBasePlotter::getAxes(bool includePrimaries)
+{
+  QList<JKQTPCoordinateAxis *> res;
+  if (includePrimaries) res<<xAxis<<yAxis;
+  for (auto& ax: secondaryXAxis) res<<ax;
+  for (auto& ax: secondaryYAxis) res<<ax;
+  return res;
+}
+
+JKQTPCoordinateAxisRef JKQTBasePlotter::addSecondaryXAxis(JKQTPHorizontalAxisBase *axis)
+{
+    const auto keys=secondaryXAxis.keys();
+    JKQTPCoordinateAxisRef ref=JKQTPSecondaryAxis;
+    if (keys.size()>0) {
+        ref=static_cast<JKQTPCoordinateAxisRef>(static_cast<int>(*std::max_element(keys.begin(), keys.end()))+1);
+    }
+    secondaryXAxis[ref]=axis;
+    axis->setParent(this);
+    return ref;
+}
+
+JKQTPCoordinateAxisRef JKQTBasePlotter::addSecondaryYAxis(JKQTPVerticalAxisBase *axis)
+{
+    const auto keys=secondaryYAxis.keys();
+    JKQTPCoordinateAxisRef ref=JKQTPSecondaryAxis;
+    if (keys.size()>0) {
+        ref=static_cast<JKQTPCoordinateAxisRef>(static_cast<int>(*std::max_element(keys.begin(), keys.end()))+1);
+    }
+    secondaryYAxis[ref]=axis;
+    axis->setParent(this);
+    return ref;
 }
 
 QAction *JKQTBasePlotter::getActionSavePlot() const {
@@ -4565,13 +4718,14 @@ void JKQTBasePlotter::saveUserSettings() const
 
 
 
-void JKQTBasePlotter::getGraphsXMinMax(double& minx, double& maxx, double& smallestGreaterZero) {
+bool JKQTBasePlotter::getGraphsXMinMax(double& minx, double& maxx, double& smallestGreaterZero, const PlotElementPreciate& predicate) {
     bool start=true;
     minx=0;
     maxx=0;
     smallestGreaterZero=0;
+    size_t count=0;
     for (int i=0; i<graphs.size(); i++) {
-        if (graphs[i]->isVisible()) {
+        if (graphs[i]->isVisible() && predicate(graphs[i])) {
 
             double gminx=0;
             double gmaxx=0;
@@ -4589,6 +4743,7 @@ void JKQTBasePlotter::getGraphsXMinMax(double& minx, double& maxx, double& small
                 //std::cout<<"         "<<i<<": gminx="<<gminx<<"  gmaxx="<<gmaxx<<"   minx="<<minx<<" maxx="<<maxx<<std::endl;
 
                 start=false;
+                count++;
             } else {
                 //std::cout<<"      -> "<<i<<": "<<graphs[i]->getTitle().toStdString()<<": FALSE"<<std::endl;
             }
@@ -4596,15 +4751,17 @@ void JKQTBasePlotter::getGraphsXMinMax(double& minx, double& maxx, double& small
             //std::cout<<"      -> "<<i<<": "<<graphs[i]->getTitle().toStdString()<<": INVISIBLE"<<std::endl;
         }
     }
+    return count>0;
 }
 
-void JKQTBasePlotter::getGraphsYMinMax(double& miny, double& maxy, double& smallestGreaterZero) {
+bool JKQTBasePlotter::getGraphsYMinMax(double& miny, double& maxy, double& smallestGreaterZero, const PlotElementPreciate &predicate) {
     bool start=true;
     miny=0;
     maxy=0;
     smallestGreaterZero=0;
+    size_t count=0;
     for (int i=0; i<graphs.size(); i++) {
-        if (graphs[i]->isVisible()) {
+        if (graphs[i]->isVisible() && predicate(graphs[i])) {
             double gminy=0;
             double gmaxy=0;
             double gsmallestGreaterZero=0;
@@ -4618,105 +4775,82 @@ void JKQTBasePlotter::getGraphsYMinMax(double& miny, double& maxy, double& small
                 xvsgz=gminy; if ((xvsgz>10.0*DBL_MIN)&&((smallestGreaterZero<10.0*DBL_MIN) || (xvsgz<smallestGreaterZero))) smallestGreaterZero=xvsgz;
 
                 start=false;
+                count++;
             }
         }
     }
+    return count>0;
 }
 
 
 void JKQTBasePlotter::zoomToFit(bool zoomX, bool zoomY, bool includeX0, bool includeY0, double scaleX, double scaleY) {
    // std::cout<<"JKQTBasePlotter::zoomToFit():\n";
     if (graphs.size()<=0) return;
-    if (zoomX) {
+    auto calcLocScaling=[](JKQTPCoordinateAxis* axis, double &xxmin, double&xxmax, double&xsmallestGreaterZero, bool include0, double scale) -> bool {
-        double xxmin=0;
-        double xxmax=0;
-        double xsmallestGreaterZero=0;
-        getGraphsXMinMax(xxmin, xxmax, xsmallestGreaterZero);
-        //std::cout<<"   xxmin="<<xxmin<<"   xxmax="<<xxmax<<std::endl;
         if (JKQTPIsOKFloat(xxmin) && JKQTPIsOKFloat(xxmax)) {
             bool doScale=true;
             if (fabs(xxmin-xxmax)<1e-305) {
-                xxmin=xAxis->getMin();
+                xxmin=axis->getMin();
-                xxmax=xAxis->getMax();
+                xxmax=axis->getMax();
                 doScale=false;
             }
-            if (xAxis->isLogAxis()) {
+            if (axis->isLogAxis()) {
                 if ((xxmin<=1e-305)&&(xxmax<=1e-305)) {xxmin=0.1; xxmax=1.0; }
                 else if ((xxmin<=1e-305)&&(xxmax>0)) {
                     if (xsmallestGreaterZero>10.0*DBL_MIN) xxmin=xsmallestGreaterZero;
-                    else xxmin=xxmax/xAxis->getLogAxisBase();
+                    else xxmin=xxmax/axis->getLogAxisBase();
                 }
                 if (doScale) {
-                    double d=scaleX*(log(xxmax)-log(xxmin));  // new width
+                    double d=scale*(log(xxmax)-log(xxmin));  // new width
                     double c=(log(xxmax)+log(xxmin))/2.0;     // center of interval
                     xxmin=exp(c-d/2.0);
                     xxmax=exp(c+d/2.0);
                 }
             } else if (doScale) {
-                double d=scaleX*(xxmax-xxmin);  // new width
+                double d=scale*(xxmax-xxmin);  // new width
                 double c=(xxmax+xxmin)/2.0;     // center of interval
                 xxmin=c-d/2.0;
                 xxmax=c+d/2.0;
             }
-            if (includeX0 && !xAxis->isLogAxis()) {
+            if (include0 && !axis->isLogAxis()) {
                 if (xxmin>0) xxmin=0;
                 else if (xxmax<0) xxmax=0;
             }
-            //std::cout<<"   => xxmin="<<xxmin<<"   xxmax="<<xxmax<<std::endl;
+
             if (JKQTPIsOKFloat(xxmin) && JKQTPIsOKFloat(xxmax)) {
-                setX(xxmin, xxmax);
+                axis->setRange(xxmin, xxmax);
             } else if (!JKQTPIsOKFloat(xxmin) && JKQTPIsOKFloat(xxmax)) {
-                setX(getXMin(), xxmax);
+                axis->setRange(axis->getMin(), xxmax);
             } else if (JKQTPIsOKFloat(xxmin) && !JKQTPIsOKFloat(xxmax)) {
-                setX(xxmin, getXMax());
+                axis->setRange(xxmin, axis->getMax());
+            }
+            return doScale;
+        }
+        return false;
+    };
+
+    if (zoomX) {
+        const auto axes=getXAxes();
+        for (auto it=axes.begin(); it!=axes.end(); ++it) {
+            double xxmin=0;
+            double xxmax=0;
+            double xsmallestGreaterZero=0;
+            if (getGraphsXMinMax(xxmin, xxmax, xsmallestGreaterZero, filterPlotElementByXAxis(it.key()))) {
+                calcLocScaling(it.value(), xxmin, xxmax, xsmallestGreaterZero, includeX0, scaleX);
             }
         }
     }
 
     if (zoomY) {
-        double yymin=0;
+        const auto axes=getYAxes();
-        double yymax=0;
+        for (auto it=axes.begin(); it!=axes.end(); ++it) {
-        double ysmallestGreaterZero=0;
+            double xxmin=0;
-        getGraphsYMinMax(yymin, yymax, ysmallestGreaterZero);
+            double xxmax=0;
-        //std::cout<<"   yymin="<<yymin<<"   yymax="<<yymax<<std::endl;
+            double xsmallestGreaterZero=0;
-        bool doScale=true;
+            if (getGraphsYMinMax(xxmin, xxmax, xsmallestGreaterZero, filterPlotElementByYAxis(it.key()))) {
-        if (fabs(yymin-yymax)<1e-305) {
+                calcLocScaling(it.value(), xxmin, xxmax, xsmallestGreaterZero, includeY0, scaleY);
-            yymin=yAxis->getMin();
-            yymax=yAxis->getMax();
-            doScale=false;
             }
-        if (yAxis->getLogAxis()) {
-            if ((yymin<=1e-305)&&(yymax<=1e-305)) {yymin=0.1; yymax=1.0; }
-            else if ((yymin<=1e-305)&&(yymax>0)) {
-                if (ysmallestGreaterZero>10.0*DBL_MIN) yymin=ysmallestGreaterZero;
-                else yymin=yymax/yAxis->getLogAxisBase();
         }
-            if (doScale) {
-                double d=scaleY*(log(yymax)-log(yymin));  // new width
-                double c=(log(yymax)+log(yymin))/2.0;     // center of interval
-                yymin=exp(c-d/2.0);
-                yymax=exp(c+d/2.0);
-            }
-        } else if (doScale) {
-            double d=scaleY*(yymax-yymin);  // new width
-            double c=(yymax+yymin)/2.0;     // center of interval
-            yymin=c-d/2.0;
-            yymax=c+d/2.0;
-        }
-        if (includeY0 && !yAxis->getLogAxis()) {
-            if (yymin>0) yymin=0;
-            else if (yymax<0) yymax=0;
-        }
-        //std::cout<<"   => yymin="<<yymin<<"   yymax="<<yymax<<std::endl;
-
-        if (JKQTPIsOKFloat(yymin) && JKQTPIsOKFloat(yymax)) {
-            setY(yymin, yymax);
-        } else if (!JKQTPIsOKFloat(yymin) && JKQTPIsOKFloat(yymax)) {
-            setY(getYMin(), yymax);
-        } else if (JKQTPIsOKFloat(yymin) && !JKQTPIsOKFloat(yymax)) {
-            setY(yymin, getYMax());
-        }
-
     }
     //std::cout<<"end of zoomToFit\n";
     //setXY(xxmin, xxmax, yymin, yymax);
@@ -5075,8 +5209,9 @@ void JKQTBasePlotter::showPlotData() {
 void JKQTBasePlotter::setEmittingSignalsEnabled(bool enabled)
 {
     emitSignals=enabled;
-    xAxis->setDoUpdateScaling(enabled);
+    for (auto ax: getAxes(true)) {
-    yAxis->setDoUpdateScaling(enabled);
+        ax->setDoUpdateScaling(enabled);
+    }
 }
 
 
@@ -5295,3 +5430,7 @@ void JKQTBasePlotter::JKQTPPen::setSymbolType(JKQTPGraphSymbols symbol)
 {
     m_symbol=symbol;
 }
+
+bool JKQTBasePlotter::filterPlotElementByXAxis::operator()(const JKQTPPlotElement *el) const { return el->getXAxisRef()==ref; }
+
+bool JKQTBasePlotter::filterPlotElementByYAxis::operator()(const JKQTPPlotElement *el) const { return el->getYAxisRef()==ref; }

lib/jkqtplotter/jkqtpbaseplotter.h

@@ -93,6 +93,7 @@ class JKQTPLOTTER_LIB_EXPORT JKQTPPaintDeviceAdapter {
         virtual QPaintDevice* createPaintdeviceMM(const QString& filename, double widthMM, double heightMM) const;
 };
 
+
 /** \brief base class for 2D plotter classes (used by the plotter widget JKQTPlotter)
  * \ingroup jkqtpplotterclasses
  *
@@ -137,12 +138,49 @@ class JKQTPLOTTER_LIB_EXPORT JKQTPPaintDeviceAdapter {
  *
  *
  * \section jkqtplotter_base_grids_baseplotter Axis Ticks and Grids
- *    - The plotting of coordinate axes and grids, as well as coordinate transforms is done by
+ *
- *      JKQTPCoordinateAxis descendents (see documentation there)
+ * \subsection jkqtplotter_base_grids_baseplotter_majoraxes Major Coordinate Axes
- *  .
+ *
+ *  JKQTBasePlotter - by default - has two major axes: A horizontal x-axis and a vertical y-axis.
+ *
+ *  The plotting of coordinate axes and grids, as well as coordinate transforms is done by
+ *  JKQTPCoordinateAxis descendents (see documentation there).
+ *
  *  If you want to set the axis properties, use getXAxis() or getYAxis() to get a pointer to the axis objects which then
  *  may be used to set the axis properties.
  *
+ * \subsection jkqtplotter_base_grids_baseplotter_secondaryaxes Secondary Coordinate Axes
+ *
+ * In addition a plot may contain secondary axes, as shown below:
+ *
+ * \image html JKQTBasePlotter_addSecondaryYAxis.png
+ *
+ * You can add additional x-axes using addSecondaryXAxis() and y-axes using addSecondaryYAxis().
+ * These functions return a JKQTPCoordinateAxisRef, which can be used to reference these axes, when
+ * calling function like getXAxis() here the default-parameter call getXAxis(JKQTPPrimaryAxis) returns
+ * the primary axis (JKQTPPrimaryAxis may be omitted) and calling getXAxis(JKQTPSecondaryAxis) will return
+ * the first secondary axis and so on.
+ *
+ * In graphs (derived from JKQTPPlotElement) you can use JKQTPPlotElement::setXAxis() and JKQTPPlotElement::setYAxis()
+ * with a JKQTPCoordinateAxisRef as parameter to tell plots to use another axis.
+ *
+ * Using a JKQTPCoordinateAxisRef instead of a pointer to a JKQTPCoordinateAxis allows to exchange the axes in the plot,
+ * while not breaking the graphs.
+ *
+ * Here is a code example of how to use secondary axes:
+ *  \code
+ *    // construct a new x-axis-object
+ *    JKQTPHorizontalAxisBase* secXAxis=new JKQTPHorizontalAxis(plot.getPlotter(), JKQTPPrimaryAxis)
+ *    // add it to the plot
+ *    auto xAxisRef2=plot.getPlotter()->addSecondaryXAxis(secXAxis);
+ *    // ... now you can access it:
+ *    plot.getXAxis(xAxisRef2)->setShowZeroAxis(false);
+ *    // ... and use it for graphs:
+ *    graph2->setXAxis(xAxisRef2);
+ *  \endcode
+ *
+ *  \see addSecondaryXAxis(), addSecondaryYAxis(), getXAxis(), getYAxis()
+ *
  *
  * \section jkqtbaseplotter_appearance_and_style Appearance & Styling of the Graph
  *
@@ -656,6 +694,13 @@ class JKQTPLOTTER_LIB_EXPORT JKQTBasePlotter: public QObject {
          */
         void drawNonGrid(JKQTPEnhancedPainter& painter, const QPoint& pos=QPoint(0,0));
 
+        /** \brief updates the secondary axes
+         *
+         *  The plot may contain (in addition to its primary axes) also secondary axes, that depend in their
+         *  scaling (min,max, ...) on the primmary axes of the plot. This function updates/recalculates the
+         *  scaling of these axes.
+         */
+        void updateSecondaryAxes();
         /** \brief emit plotUpdated() */
         void redrawPlot() { if (emitPlotSignals) emit plotUpdated(); }
 
@@ -826,15 +871,96 @@ class JKQTPLOTTER_LIB_EXPORT JKQTBasePlotter: public QObject {
         JKQTMathText* getMathText();
         /** \brief returns the internal JKQTMathText, used to render text with LaTeX markup */
         const JKQTMathText *getMathText() const;
-        /** \brief returns the x-axis objet of the plot */
+        /** \brief returns the x-axis objet of the plot
-        JKQTPHorizontalAxis *getXAxis();
+         *
-        /** \brief returns the y-axis objet of the plot */
+         *  \see \ref jkqtplotter_base_grids_baseplotter
-        JKQTPVerticalAxis* getYAxis();
+         */
-        /** \brief returns the x-axis objet of the plot */
+        JKQTPHorizontalAxisBase *getXAxis(JKQTPCoordinateAxisRef axis=JKQTPPrimaryAxis);
-        const JKQTPHorizontalAxis* getXAxis() const;
+        /** \brief returns the y-axis objet of the plot
-        /** \brief returns the y-axis objet of the plot */
+         *
-        const JKQTPVerticalAxis *getYAxis() const;
+         *  \see \ref jkqtplotter_base_grids_baseplotter
+         */
+        JKQTPVerticalAxisBase* getYAxis(JKQTPCoordinateAxisRef axis=JKQTPPrimaryAxis);
+        /** \brief returns the x-axis objet of the plot
+         *
+         *  \see \ref jkqtplotter_base_grids_baseplotter
+         */
+        const JKQTPHorizontalAxisBase* getXAxis(JKQTPCoordinateAxisRef axis=JKQTPPrimaryAxis) const;
+        /** \brief returns the y-axis objet of the plot
+         *
+         *  \see \ref jkqtplotter_base_grids_baseplotter
+         */
+        const JKQTPVerticalAxisBase *getYAxis(JKQTPCoordinateAxisRef axis=JKQTPPrimaryAxis) const;
+        /** \brief returns whether an x-axis \a axis is registered with the plotter
+         *
+         *  \note For \a axis \c ==JKQTPPrimaryAxis this function returns always \c true
+         */
+        bool hasXAxis(JKQTPCoordinateAxisRef axis=JKQTPPrimaryAxis) const;
+        /** \brief returns whether a y-axis \a axis is registered with the plotter
+         *
+         *  \note For \a axis \c ==JKQTPPrimaryAxis this function returns always \c true
+         */
+        bool hasYAxis(JKQTPCoordinateAxisRef axis=JKQTPPrimaryAxis) const;
+        /** \brief returns the set of available x-axes (including the primary, if \c true is given as parameter) */
+        QSet<JKQTPCoordinateAxisRef> getAvailableXAxisRefs(bool includePrimary=false) const;
+        /** \brief returns the set of available y-axes (including the primary, if \c true is given as parameter) */
+        QSet<JKQTPCoordinateAxisRef> getAvailableYAxisRefs(bool includePrimary=false) const;
+        /** \brief returns all available x-axes */
+        QMap<JKQTPCoordinateAxisRef, JKQTPHorizontalAxisBase*> getXAxes(bool includePrimary=true);
+        /** \brief returns all available y-axes */
+        QMap<JKQTPCoordinateAxisRef, JKQTPVerticalAxisBase*> getYAxes(bool includePrimary=true);
+        /** \brief returns all available x- or y-axes */
+        QList<JKQTPCoordinateAxis*> getAxes(bool includePrimaries=true);
 
+        /** \brief adds a secondary x-axis
+         *
+         *  \params axis the JKQTPHorizontalAxisBase object to add
+         *  \returns a reference to this axis
+         *
+         *  Usage is simple:
+         *  \code
+         *    // construct a new x-axis-object
+         *    JKQTPHorizontalAxisBase* secXAxis=new JKQTPHorizontalAxis(plot.getPlotter(), JKQTPPrimaryAxis)
+         *    // add it to the plot
+         *    auto xAxisRef2=plot.getPlotter()->addSecondaryXAxis(secXAxis);
+         *    // ... now you can access it:
+         *    plot.getXAxis(xAxisRef2)->setShowZeroAxis(false);
+         *    // ... and use it for graphs:
+         *    graph2->setXAxis(xAxisRef2);
+         *  \endcode
+         *
+         *
+         *  Here is an example output:
+         *
+         *  \image html JKQTBasePlotter_addSecondaryXAxis.png
+         *
+         *  \see \ref jkqtplotter_base_grids_baseplotter_secondaryaxes , \subpage JKQTPlotterSecondaryAxes
+         */
+        JKQTPCoordinateAxisRef addSecondaryXAxis(JKQTPHorizontalAxisBase* axis);
+        /** \brief adds a secondary y-axis
+         *
+         *  \params axis the JKQTPVerticalAxisBase object to add
+         *  \returns a reference to this axis
+         *
+         *  Usage is simple:
+         *  \code
+         *    // construct a new y-axis-object
+         *    JKQTPVerticalAxisBase* secYAxis=new JKQTPVerticalAxis(plot.getPlotter(), JKQTPPrimaryAxis)
+         *    // add it to the plot
+         *    auto yAxisRef2=plot.getPlotter()->addSecondaryYAxis(secYAxis);
+         *    // ... now you can access it:
+         *    plot.getYAxis(yAxisRef2)->setShowZeroAxis(false);
+         *    // ... and use it for graphs:
+         *    graph2->setYAxis(yAxisRef2);
+         *  \endcode
+         *
+         *  Here is an example output:
+         *
+         *  \image html JKQTBasePlotter_addSecondaryYAxis.png
+         *
+         *  \see \ref jkqtplotter_base_grids_baseplotter_secondaryaxes , \subpage JKQTPlotterSecondaryAxes
+         */
+        JKQTPCoordinateAxisRef addSecondaryYAxis(JKQTPVerticalAxisBase* axis);
 
         /** \copydoc actSavePlot */
         QAction* getActionSavePlot() const;
@@ -953,22 +1079,62 @@ class JKQTPLOTTER_LIB_EXPORT JKQTBasePlotter: public QObject {
             }
         }
 
+        /** \brief Functor which can be used as filter predicate for getGraphsXMinMax() or getGraphsYMinMax()
+         *
+         *  \see getGraphsXMinMax(), getGraphsYMinMax(), allPlotElements
+         */
+        typedef std::function<bool(const JKQTPPlotElement*)> PlotElementPreciate;
+
+        /** \brief Functor which does not apply any filter to JKQTPPlotElement, e.g. in getGraphsXMinMax() or getGraphsYMinMax()
+         *
+         *  \see getGraphsXMinMax(), getGraphsYMinMax(), PlotElementPreciate
+         */
+        struct JKQTPLOTTER_LIB_EXPORT allPlotElements {
+            inline bool operator()(const JKQTPPlotElement*) const { return true; };
+        };
+        /** \brief filter functor which accepts only those JKQTPPlotElement where JKQTPPlotElement::getXAxisRef()
+         *         returns the JKQTPCoordinateAxisRef supplied to the constructor, e.g. in getGraphsXMinMax() or getGraphsYMinMax()
+         *
+         *  \see getGraphsXMinMax(), getGraphsYMinMax(), PlotElementPreciate
+         */
+        struct JKQTPLOTTER_LIB_EXPORT filterPlotElementByXAxis {
+            inline explicit filterPlotElementByXAxis(JKQTPCoordinateAxisRef ref_): ref(ref_) {};
+            inline bool operator()(const JKQTPPlotElement* el) const;
+        private:
+            JKQTPCoordinateAxisRef ref;
+        };
+        /** \brief filter functor which accepts only those JKQTPPlotElement where JKQTPPlotElement::getYAxisRef()
+         *         returns the JKQTPCoordinateAxisRef supplied to the constructor, e.g. in getGraphsXMinMax() or getGraphsYMinMax()
+         *
+         *  \see getGraphsXMinMax(), getGraphsYMinMax(), PlotElementPreciate
+         */
+        struct JKQTPLOTTER_LIB_EXPORT filterPlotElementByYAxis {
+            inline explicit filterPlotElementByYAxis(JKQTPCoordinateAxisRef ref_): ref(ref_) {};
+            inline bool operator()(const JKQTPPlotElement* el) const;
+        private:
+            JKQTPCoordinateAxisRef ref;
+        };
         /** \brief get the maximum and minimum x-value over all graphs in the plot
          *  \param[out] minx smallest x value
          *  \param[out] maxx largest x value
          *  \param[out] smallestGreaterZero smallest data point which is >0 (needed for scaling of logarithmic axes)
+         *  \param predicate a PlotElementPreciate, which can be used to limit the JKQTPPlotElement to be evaluated
+         *  \returns \c true if at least one matching graph was found and evaluated succcessfully
          *
          * The result is given in the two parameters which are call-by-reference parameters!
          */
-        void getGraphsXMinMax(double& minx, double& maxx, double& smallestGreaterZero);
+        bool getGraphsXMinMax(double& minx, double& maxx, double& smallestGreaterZero, const PlotElementPreciate &predicate=allPlotElements());
         /** \brief get the maximum and minimum y-value over all graphs in the plot
          *  \param[out] miny smallest y value
          *  \param[out] maxy largest y value
          *  \param[out] smallestGreaterZero smallest data point which is >0 (needed for scaling of logarithmic axes)
+         *  \param predicate a PlotElementPreciate, which can be used to limit the JKQTPPlotElement to be evaluated
+         *  \returns \c true if at least one matching graph was found and evaluated succcessfully
          *
          * The result is given in the two parameters which are call-by-reference parameters!
          */
-        void getGraphsYMinMax(double& miny, double& maxy, double& smallestGreaterZero);
+        bool getGraphsYMinMax(double& miny, double& maxy, double& smallestGreaterZero, const PlotElementPreciate &predicate=allPlotElements());
+
 
 
         /** \brief denotes, which axes to synchronize in synchronizeToMaster() */
@@ -1226,6 +1392,9 @@ class JKQTPLOTTER_LIB_EXPORT JKQTBasePlotter: public QObject {
          *
          *  \param xminn absolute minimum of x-axis
          *  \param xmaxx absolute maximum of x-axis
+         *  \param affectsSecondaryAxes if \c true, the secondary axes are affectedtoo, by using a relative zooming scheme,
+         *                              i.e. if a major axis range shrinks by 50%, also the secondary ranges shrink by 50%
+         *                              [default: \c false]
          *
          * \note You cannot expand the x-range outside the absolute x-range set e.g. by setAbsoluteX()!
          *       Also the range will be limited to possible values (e.g. to positive values if you use
@@ -1236,12 +1405,15 @@ class JKQTPLOTTER_LIB_EXPORT JKQTBasePlotter: public QObject {
          *
          * \see setY(), setXY(), zoomToFit(), setAbsoluteXY(), JKQTPlotter::setY()
          */
-        void setX(double xminn, double xmaxx);
+        void setX(double xminn, double xmaxx, bool affectsSecondaryAxes=false);
 
         /** \brief sets the y-range of the plot (minimum and maximum y-value on the y-axis)
          *
          *  \param yminn absolute minimum of y-axis
          *  \param ymaxx absolute maximum of y-axis
+         *  \param affectsSecondaryAxes if \c true, the secondary axes are affectedtoo, by using a relative zooming scheme,
+         *                              i.e. if a major axis range shrinks by 50%, also the secondary ranges shrink by 50%
+         *                              [default: \c false]
          *
          * \note You cannot expand the y-range outside the absolute y-range set e.g. by setAbsoluteY()!
          *       Also the range will be limited to possible values (e.g. to positive values if you use
@@ -1252,7 +1424,7 @@ class JKQTPLOTTER_LIB_EXPORT JKQTBasePlotter: public QObject {
          *
          * \see setX(), setXY(), zoomToFit(), setAbsoluteXY(), JKQTPlotter::setX()
          */
-        void setY(double yminn, double ymaxx);
+        void setY(double yminn, double ymaxx, bool affectsSecondaryAxes=false);
 
         /** \brief sets the x- and y-range of the plot (minimum and maximum values on the x-/y-axis)
          *
@@ -1260,6 +1432,9 @@ class JKQTPLOTTER_LIB_EXPORT JKQTBasePlotter: public QObject {
          *  \param xmaxx absolute maximum of x-axis
          *  \param yminn absolute minimum of y-axis
          *  \param ymaxx absolute maximum of y-axis
+         *  \param affectsSecondaryAxes if \c true, the secondary axes are affectedtoo, by using a relative zooming scheme,
+         *                              i.e. if a major axis range shrinks by 50%, also the secondary ranges shrink by 50%
+         *                              [default: \c false]
          *
          * \note You cannot expand the ranges outside the absolute ranges set e.g. by setAbsoluteXY()!
          *       Also the range will be limited to possible values (e.g. to positive values if you use
@@ -1270,7 +1445,7 @@ class JKQTPLOTTER_LIB_EXPORT JKQTBasePlotter: public QObject {
          *
          * \see setX(), setX(), zoomToFit(), setAbsoluteXY(), JKQTPlotter::setXY()
          */
-        void setXY(double xminn, double xmaxx, double yminn, double ymaxx);
+        void setXY(double xminn, double xmaxx, double yminn, double ymaxx, bool affectsSecondaryAxes=false);
 
         /** \brief sets absolutely limiting x-range of the plot
          *
@@ -1873,8 +2048,12 @@ class JKQTPLOTTER_LIB_EXPORT JKQTBasePlotter: public QObject {
 
         /** \brief object used for the x-axis */
         JKQTPHorizontalAxis* xAxis;
+        /** \brief objects used a secondary x-axes */
+        QMap<JKQTPCoordinateAxisRef, JKQTPHorizontalAxisBase*> secondaryXAxis;
         /** \brief object used for the y-axis */
         JKQTPVerticalAxis* yAxis;
+        /** \brief objects used a secondary y-axes */
+        QMap<JKQTPCoordinateAxisRef, JKQTPVerticalAxisBase*> secondaryYAxis;
 
         /** \brief filename for the ini file in which to save the user settings
          *  \see jkqtplotter_base_userprops
@@ -2031,6 +2210,40 @@ class JKQTPLOTTER_LIB_EXPORT JKQTBasePlotter: public QObject {
           */
         double internalPlotBorderRight_notIncludingOutsidePlotSections;
 
+
+        /** \brief <b>calculated value:</b> free space between widget top border and (plot+drawOutside) top border (including coordinate axes)
+         * \internal
+         *
+         * \image html plot_widget_orientation.png
+         *
+         * \note This property is an intermediate storage for calculated values. Do not change directly!
+         */
+        double internalPlotBorderTop_notIncludingAxisAndOutsidePlotSections;
+        /** \brief <b>calculated value:</b> free space between widget left border and (plot+drawOutside) left border (including coordinate axes)
+         * \internal
+         *
+         * \image html plot_widget_orientation.png
+         *
+         * \note This property is an intermediate storage for calculated values. Do not change directly!
+          */
+        double internalPlotBorderLeft_notIncludingAxisAndOutsidePlotSections;
+        /** \brief <b>calculated value:</b> free space between widget right border and (plot+drawOutside) right border (including coordinate axes)
+         * \internal
+         *
+         * \image html plot_widget_orientation.png
+         *
+         * \note This property is an intermediate storage for calculated values. Do not change directly!
+          */
+        double internalPlotBorderBottom_notIncludingAxisAndOutsidePlotSections;
+        /** \brief <b>calculated value:</b> free space between widget bottom border and (plot+drawOutside) bottom border (including coordinate axes)
+         * \internal
+         *
+         * \image html plot_widget_orientation.png
+         *
+         * \note This property is an intermediate storage for calculated values. Do not change directly!
+          */
+        double internalPlotBorderRight_notIncludingAxisAndOutsidePlotSections;
+
         /** \brief <b>calculated value:</b> plot width in pixel inside the widget (calculated by calcPlotScaling() from plotBorderLeft, plotBorderRight and widgetWidth)
          *
          * \image html plot_widget_orientation.png

lib/jkqtplotter/jkqtpbaseplotterstyle.cpp

@@ -31,6 +31,7 @@ JKQTBasePlotterStyle::JKQTBasePlotterStyle():
     keyStyle(*this),
     xAxisStyle(*this),
     yAxisStyle(*this),
+    secondaryAxisSeparation(6),
     rightColorbarAxisStyle(*this),
     topColorbarAxisStyle(*this),
     graphsStyle(*this)
@@ -63,6 +64,7 @@ void JKQTBasePlotterStyle::loadSettings(const QSettings &settings, const QString
     defaultTextColor=jkqtp_String2QColor(settings.value(group+"text_default_color", jkqtp_QColor2String(defaultStyle.defaultTextColor)).toString());
     defaultFontSize=settings.value(group+"text_default_size", defaultStyle.defaultFontSize).toDouble();
     defaultFontName=settings.value(group+"text_default_font_name", defaultStyle.defaultFontName).toString();
+    secondaryAxisSeparation=settings.value(group+"secondary_axis_separation", defaultStyle.secondaryAxisSeparation).toDouble();
 
     keyStyle.loadSettings(settings, group+"key/", defaultStyle.keyStyle);
     xAxisStyle.loadSettings(settings, group+"axis_x/", defaultStyle.xAxisStyle);
@@ -101,6 +103,7 @@ void JKQTBasePlotterStyle::saveSettings(QSettings &settings, const QString &grou
     settings.setValue(group+"plot_frame_color", jkqtp_QColor2String(plotFrameColor));
     settings.setValue(group+"plot_frame_width", plotFrameWidth);
     settings.setValue(group+"plot_frame_rounded", plotFrameRounding);
+    settings.setValue(group+"secondary_axis_separation", secondaryAxisSeparation);
 
     keyStyle.saveSettings(settings, group+"key/");
     xAxisStyle.saveSettings(settings, group+"axis_x/");

lib/jkqtplotter/jkqtpbaseplotterstyle.h

@@ -160,6 +160,8 @@ class JKQTPLOTTER_LIB_EXPORT JKQTBasePlotterStyle {
         JKQTPCoordinateAxisStyle xAxisStyle;
         /** \brief style of the y-axis of the main coordinate system */
         JKQTPCoordinateAxisStyle yAxisStyle;
+        /** \brief separation between two seondary axes in pt */
+        double secondaryAxisSeparation;
         /** \brief style of the coordinate axes used to display colorbars in the right */
         JKQTPColorbarCoordinateAxisStyle rightColorbarAxisStyle;
         /** \brief style of the coordinate axes used to display colorbars at the top */

lib/jkqtplotter/jkqtpcoordinateaxes.cpp

@@ -82,6 +82,7 @@ void JKQTPCoordinateAxis::setParent(JKQTBasePlotter* parent) {
 void JKQTPCoordinateAxis::redrawPlot() {
     //if (paramsChanged)  {
         calcPlotScaling();
+        parent->updateSecondaryAxes();
         parent->redrawPlot();
     //}
 }
@@ -1140,6 +1141,18 @@ void JKQTPCoordinateAxis::setTickLabelColor(QColor c)  {
     redrawPlot();
 }
 
+void JKQTPCoordinateAxis::setColor(QColor c)
+{
+    setAxisColor(c);
+    setGridColor(c.lighter());
+    setMinorGridColor(c.lighter());
+    setLabelColor(c);
+    setMinorTickColor(c);
+    setMinorTickLabelColor(c);
+    setTickColor(c);
+    setTickLabelColor(c);
+}
+
 std::pair<QSizeF,QSizeF> JKQTPCoordinateAxis::getSize0(JKQTPEnhancedPainter &/*painter*/)
 {
     return std::pair<QSizeF,QSizeF>(QSizeF(0,0),QSizeF(0,0));
@@ -1276,7 +1289,7 @@ double JKQTPCoordinateAxis::getZeroAxisPos(bool *drawZeroAxis) {
 
 
 
-JKQTPVerticalAxis::JKQTPVerticalAxis(JKQTBasePlotter* parent):
+JKQTPVerticalAxisBase::JKQTPVerticalAxisBase(JKQTBasePlotter* parent):
     JKQTPCoordinateAxis(parent)
 {
     //axisPrefix="yaxis_";
@@ -1288,15 +1301,8 @@ JKQTPVerticalAxis::JKQTPVerticalAxis(JKQTBasePlotter* parent):
     }
 }
 
-double JKQTPVerticalAxis::getParentPlotWidth() const {
-    return parent->getPlotHeight();
-}
 
-double JKQTPVerticalAxis::getParentPlotOffset() const {
+std::pair<QSizeF,QSizeF> JKQTPVerticalAxisBase::getSize0(JKQTPEnhancedPainter& painter) {
-    return parent->getInternalPlotBorderTop();
-}
-
-std::pair<QSizeF,QSizeF> JKQTPVerticalAxis::getSize0(JKQTPEnhancedPainter& painter) {
     if (axisStyle.drawMode0==JKQTPCADMnone) return std::pair<QSizeF,QSizeF>(QSizeF(0,0),QSizeF(0,0));
     double ptwidth=0;
     double ptwidth_r=0;
@@ -1326,7 +1332,7 @@ std::pair<QSizeF,QSizeF> JKQTPVerticalAxis::getSize0(JKQTPEnhancedPainter& paint
 }
 
 
-QSizeF JKQTPVerticalAxis::getSize1(JKQTPEnhancedPainter& painter) {
+QSizeF JKQTPVerticalAxisBase::getSize1(JKQTPEnhancedPainter& painter) {
     if (axisStyle.drawMode1==JKQTPCADMnone) return QSize(0,0);
     double ptwidth=axisStyle.axisLineOffset;
     const double arrowSize=((axisStyle.drawMode1&(JKQTPCADMMinArrow|JKQTPCADMMinFilledArrow|JKQTPCADMMaxArrow|JKQTPCADMMaxFilledArrow))!=int(0))?(axisStyle.getArrowSize(painter, parent)/2.0):0.0;
@@ -1346,7 +1352,7 @@ QSizeF JKQTPVerticalAxis::getSize1(JKQTPEnhancedPainter& painter) {
     return QSizeF(qMax(parent->pt2px(painter, ptwidth)+labwidth, arrowSize), getParentPlotWidth()).expandedTo(getSize0(painter).first);
 }
 
-QSizeF JKQTPVerticalAxis::getSize2(JKQTPEnhancedPainter& painter) {
+QSizeF JKQTPVerticalAxisBase::getSize2(JKQTPEnhancedPainter& painter) {
     if (axisStyle.drawMode2==JKQTPCADMnone) return QSize(0,0);
     double ptwidth=axisStyle.axisLineOffset;
     const double arrowSize=((axisStyle.drawMode2&(JKQTPCADMMinArrow|JKQTPCADMMinFilledArrow|JKQTPCADMMaxArrow|JKQTPCADMMaxFilledArrow))!=int(0))?(axisStyle.getArrowSize(painter, parent)/2.0):0.0;
@@ -1366,26 +1372,7 @@ QSizeF JKQTPVerticalAxis::getSize2(JKQTPEnhancedPainter& painter) {
     return QSizeF(qMax(arrowSize, parent->pt2px(painter, ptwidth)+labwidth), getParentPlotWidth()).expandedTo(getSize0(painter).second);
 }
 
-
+void JKQTPVerticalAxisBase::drawGrids(JKQTPEnhancedPainter& painter) {
-double JKQTPVerticalAxis::getParentOtheraxisOffset() const {
-    return parent->x2p(parent->getXMin());
-}
-
-double JKQTPVerticalAxis::parentOtherAxisX2P(double x) const
-{
-    return parent->x2p(x);
-}
-
-double JKQTPVerticalAxis::getParentOtheraxisWidth() const {
-    return fabs(parent->x2p(parent->getXMax())-parent->x2p(parent->getXMin()));
-}
-
-bool JKQTPVerticalAxis::getParentOtheraxisInverted() const
-{
-    return parent->getXAxis()->getInverted();
-}
-
-void JKQTPVerticalAxis::drawGrids(JKQTPEnhancedPainter& painter) {
     //qDebug()<<"  start JKQTPVerticalAxis::drawGrids(";
     painter.save(); auto __finalpaint=JKQTPFinally([&painter]() {painter.restore();});
     QPen pg=painter.pen();
@@ -1459,7 +1446,7 @@ void JKQTPVerticalAxis::drawGrids(JKQTPEnhancedPainter& painter) {
     //qDebug()<<"    end JKQTPVerticalAxis::drawGrids(";
 }
 
-void JKQTPVerticalAxis::drawTickLabel1(JKQTPEnhancedPainter &painter, double xx, double yy, double labelOffset, const QString& label, double fontSize, bool isMinor)
+void JKQTPVerticalAxisBase::drawTickLabel1(JKQTPEnhancedPainter &painter, double xx, double yy, double labelOffset, const QString& label, double fontSize, bool isMinor)
 {
     getParentMathText()->setFontSize(fontSize*parent->getFontSizeMultiplier());
     getParentMathText()->setFontSpecial(getParent()->getCurrentPlotterStyle().defaultFontName);
@@ -1498,7 +1485,7 @@ void JKQTPVerticalAxis::drawTickLabel1(JKQTPEnhancedPainter &painter, double xx,
     }
 }
 
-void JKQTPVerticalAxis::drawTickLabel2(JKQTPEnhancedPainter &painter, double xx, double yy, double labelOffset, const QString &label, double fontSize, bool isMinor)
+void JKQTPVerticalAxisBase::drawTickLabel2(JKQTPEnhancedPainter &painter, double xx, double yy, double labelOffset, const QString &label, double fontSize, bool isMinor)
 {
     getParentMathText()->setFontSize(fontSize*parent->getFontSizeMultiplier());
     getParentMathText()->setFontSpecial(getParent()->getCurrentPlotterStyle().defaultFontName);
@@ -1540,7 +1527,7 @@ void JKQTPVerticalAxis::drawTickLabel2(JKQTPEnhancedPainter &painter, double xx,
 }
 
 
-void JKQTPVerticalAxis::drawAxisLabel1(JKQTPEnhancedPainter &painter, double left, double bottom, QSizeF labelMax, JKQTPCADrawMode drawMode) {
+void JKQTPVerticalAxisBase::drawAxisLabel1(JKQTPEnhancedPainter &painter, double left, double bottom, QSizeF labelMax, JKQTPCADrawMode drawMode) {
     double labelOffset=parent->pt2px(painter, axisStyle.labelDistance);
     if (drawMode.testFlag(JKQTPCADMTicks)) labelOffset+=parent->pt2px(painter, axisStyle.tickOutsideLength);
     if (drawMode.testFlag(JKQTPCADMTickLabels)) {
@@ -1586,7 +1573,7 @@ void JKQTPVerticalAxis::drawAxisLabel1(JKQTPEnhancedPainter &painter, double lef
     painter.resetTransform();
 }
 
-void JKQTPVerticalAxis::drawAxisLabel2(JKQTPEnhancedPainter &painter, double right, double bottom, QSizeF labelMax, JKQTPCADrawMode drawMode) {
+void JKQTPVerticalAxisBase::drawAxisLabel2(JKQTPEnhancedPainter &painter, double right, double bottom, QSizeF labelMax, JKQTPCADrawMode drawMode) {
     double labelOffset=parent->pt2px(painter, axisStyle.labelDistance);
     if (drawMode.testFlag(JKQTPCADMTicks)) labelOffset+=parent->pt2px(painter, axisStyle.tickOutsideLength);
     if (drawMode.testFlag(JKQTPCADMTickLabels)) {
@@ -1633,7 +1620,7 @@ void JKQTPVerticalAxis::drawAxisLabel2(JKQTPEnhancedPainter &painter, double rig
     painter.resetTransform();
 }
 
-void JKQTPVerticalAxis::drawAxes(JKQTPEnhancedPainter& painter) {
+void JKQTPVerticalAxisBase::drawAxes(JKQTPEnhancedPainter& painter, int move1, int move2) {
 #ifdef JKQTBP_AUTOTIMER
     JKQTPAutoOutputTimer jkaat(QString("JKQTPEnhancedPainter[%1]::drawAxes()").arg(objectName()));
 #endif
@@ -1657,8 +1644,8 @@ void JKQTPVerticalAxis::drawAxes(JKQTPEnhancedPainter& painter) {
         right=getParentOtheraxisOffset()+getParentOtheraxisWidth();//;
     }
     // move axes outside plot rectangle, if required
-    left-=parent->pt2px(painter, axisStyle.axisLineOffset);
+    left-=parent->pt2px(painter, axisStyle.axisLineOffset)+move1;
-    right+=parent->pt2px(painter, axisStyle.axisLineOffset);
+    right+=parent->pt2px(painter, axisStyle.axisLineOffset)+move2;
 
 
     double ticklabelOffset1PT=axisStyle.tickLabelDistance; // offset of tick labels from axis 1
@@ -1912,9 +1899,56 @@ void JKQTPVerticalAxis::drawAxes(JKQTPEnhancedPainter& painter) {
 
 
 
+JKQTPVerticalAxis::JKQTPVerticalAxis(JKQTBasePlotter* parent, JKQTPCoordinateAxisRef otherAxisRef_):
+    JKQTPVerticalAxisBase(parent), otherAxisRef(otherAxisRef_)
+{
+    //axisPrefix="yaxis_";
+    scaleSign=-1;
+    if (parent) {
+        axisStyle=parent->getCurrentPlotterStyle().yAxisStyle;
+    } else {
+        axisStyle=JKQTPGetSystemDefaultBaseStyle().yAxisStyle;
+    }
+}
+
+double JKQTPVerticalAxis::getParentPlotWidth() const {
+    return parent->getPlotHeight();
+}
+
+double JKQTPVerticalAxis::getParentPlotOffset() const {
+    return parent->getInternalPlotBorderTop();
+}
+
+double JKQTPVerticalAxis::getParentOtheraxisOffset() const {
+    return getOtherAxis()->x2p(getOtherAxis()->getMin());
+}
+
+double JKQTPVerticalAxis::parentOtherAxisX2P(double x) const
+{
+    return getOtherAxis()->x2p(x);
+}
+
+JKQTPCoordinateAxisRef JKQTPVerticalAxis::getOtherAxisRef() const {
+    return otherAxisRef;
+}
+
+const JKQTPCoordinateAxis *JKQTPVerticalAxis::getOtherAxis() const {
+    return parent->getXAxis(otherAxisRef);
+}
+
+double JKQTPVerticalAxis::getParentOtheraxisWidth() const {
+    return fabs(getOtherAxis()->x2p(getOtherAxis()->getMax())-getOtherAxis()->x2p(getOtherAxis()->getMin()));
+}
+
+bool JKQTPVerticalAxis::getParentOtheraxisInverted() const
+{
+    return getOtherAxis()->getInverted();
+}
+
+
 
 JKQTPVerticalIndependentAxis::JKQTPVerticalIndependentAxis(double _axisOffset, double _axisWidth, double _otherAxisOffset, double _otherAxisWidth, JKQTBasePlotter* parent):
-    JKQTPVerticalAxis(parent),
+    JKQTPVerticalAxisBase(parent),
     axisOffset(_axisOffset),
     axisWidth(_axisWidth),
     otherAxisWidth(_otherAxisOffset),
@@ -1992,7 +2026,7 @@ double JKQTPVerticalIndependentAxis::parentOtherAxisX2P(double x) const
 
 
 
-JKQTPHorizontalAxis::JKQTPHorizontalAxis(JKQTBasePlotter* parent):
+JKQTPHorizontalAxisBase::JKQTPHorizontalAxisBase(JKQTBasePlotter* parent):
     JKQTPCoordinateAxis(parent)
 {
     //axisPrefix="xaxis_";
@@ -2005,15 +2039,8 @@ JKQTPHorizontalAxis::JKQTPHorizontalAxis(JKQTBasePlotter* parent):
 
 }
 
-double JKQTPHorizontalAxis::getParentPlotWidth() const {
-    return parent->getPlotWidth();
-}
 
-double JKQTPHorizontalAxis::getParentPlotOffset() const {
+std::pair<QSizeF,QSizeF> JKQTPHorizontalAxisBase::getSize0(JKQTPEnhancedPainter& painter) {
-    return parent->getInternalPlotBorderLeft();
-}
-
-std::pair<QSizeF,QSizeF> JKQTPHorizontalAxis::getSize0(JKQTPEnhancedPainter& painter) {
     if (axisStyle.drawMode0==JKQTPCADMnone) return std::pair<QSizeF,QSizeF>(QSizeF(0,0),QSizeF(0,0));
     double ptheight=0;
     double ptheight_t=0;
@@ -2043,7 +2070,7 @@ std::pair<QSizeF,QSizeF> JKQTPHorizontalAxis::getSize0(JKQTPEnhancedPainter& pai
                 );
 }
 
-QSizeF JKQTPHorizontalAxis::getSize1(JKQTPEnhancedPainter& painter) {
+QSizeF JKQTPHorizontalAxisBase::getSize1(JKQTPEnhancedPainter& painter) {
     if (axisStyle.drawMode1==JKQTPCADMnone) return QSize(0,0);
     double ptheight=axisStyle.axisLineOffset;
     const double arrowSize=((axisStyle.drawMode1&(JKQTPCADMMinArrow|JKQTPCADMMinFilledArrow|JKQTPCADMMaxArrow|JKQTPCADMMaxFilledArrow))!=int(0))?(axisStyle.getArrowSize(painter, parent)/2.0):0.0;
@@ -2063,7 +2090,7 @@ QSizeF JKQTPHorizontalAxis::getSize1(JKQTPEnhancedPainter& painter) {
     return QSizeF(getParentPlotWidth(), qMax(arrowSize,parent->pt2px(painter, ptheight)+labheight)).expandedTo(getSize0(painter).first);
 }
 
-QSizeF JKQTPHorizontalAxis::getSize2(JKQTPEnhancedPainter& painter) {
+QSizeF JKQTPHorizontalAxisBase::getSize2(JKQTPEnhancedPainter& painter) {
     if (axisStyle.drawMode2==JKQTPCADMnone) return QSize(0,0);
     double ptheight=axisStyle.axisLineOffset;
     const double arrowSize=((axisStyle.drawMode2&(JKQTPCADMMinArrow|JKQTPCADMMinFilledArrow|JKQTPCADMMaxArrow|JKQTPCADMMaxFilledArrow))!=int(0))?(axisStyle.getArrowSize(painter, parent)/2.0):0.0;
@@ -2084,24 +2111,7 @@ QSizeF JKQTPHorizontalAxis::getSize2(JKQTPEnhancedPainter& painter) {
 }
 
 
-double JKQTPHorizontalAxis::getParentOtheraxisOffset() const {
+void JKQTPHorizontalAxisBase::drawGrids(JKQTPEnhancedPainter& painter) {
-    return parent->y2p(parent->getYMax());
-}
-
-double JKQTPHorizontalAxis::parentOtherAxisX2P(double x) const
-{
-    return parent->y2p(x);
-}
-double JKQTPHorizontalAxis::getParentOtheraxisWidth() const {
-    return fabs(parent->y2p(parent->getYMax())-parent->y2p(parent->getYMin()));
-}
-
-bool JKQTPHorizontalAxis::getParentOtheraxisInverted() const
-{
-    return parent->getYAxis()->getInverted();
-}
-
-void JKQTPHorizontalAxis::drawGrids(JKQTPEnhancedPainter& painter) {
     painter.save(); auto __finalpaint=JKQTPFinally([&painter]() {painter.restore();});
     //double right=x2p(axismax);
     //double left=x2p(axismin);
@@ -2165,7 +2175,7 @@ void JKQTPHorizontalAxis::drawGrids(JKQTPEnhancedPainter& painter) {
 }
 
 
-void JKQTPHorizontalAxis::drawTickLabel1(JKQTPEnhancedPainter &painter, double xx, double yy, double labelOffset, const QString &label, double fontSize, double ascentMax, double /*descentMax*/, bool isMinor)
+void JKQTPHorizontalAxisBase::drawTickLabel1(JKQTPEnhancedPainter &painter, double xx, double yy, double labelOffset, const QString &label, double fontSize, double ascentMax, double /*descentMax*/, bool isMinor)
 {
     getParentMathText()->setFontSize(fontSize*parent->getFontSizeMultiplier());
     getParentMathText()->setFontSpecial(getParent()->getCurrentPlotterStyle().defaultFontName);
@@ -2194,7 +2204,7 @@ void JKQTPHorizontalAxis::drawTickLabel1(JKQTPEnhancedPainter &painter, double x
     }
 }
 
-void JKQTPHorizontalAxis::drawTickLabel2(JKQTPEnhancedPainter &painter, double xx, double yy, double labelOffset, const QString &label, double fontSize, double /*ascentMax*/, double descentMax, bool isMinor)
+void JKQTPHorizontalAxisBase::drawTickLabel2(JKQTPEnhancedPainter &painter, double xx, double yy, double labelOffset, const QString &label, double fontSize, double /*ascentMax*/, double descentMax, bool isMinor)
 {
     getParentMathText()->setFontSize(fontSize*parent->getFontSizeMultiplier());
     getParentMathText()->setFontSpecial(getParent()->getCurrentPlotterStyle().defaultFontName);
@@ -2223,7 +2233,7 @@ void JKQTPHorizontalAxis::drawTickLabel2(JKQTPEnhancedPainter &painter, double x
 }
 
 
-void JKQTPHorizontalAxis::drawAxisLabel1(JKQTPEnhancedPainter &painter, double left, double bottom, QSizeF labelMax, JKQTPCADrawMode drawMode) {
+void JKQTPHorizontalAxisBase::drawAxisLabel1(JKQTPEnhancedPainter &painter, double left, double bottom, QSizeF labelMax, JKQTPCADrawMode drawMode) {
     double labelOffset=parent->pt2px(painter, axisStyle.labelDistance);
     if (drawMode.testFlag(JKQTPCADMTicks)) labelOffset+=parent->pt2px(painter, axisStyle.tickOutsideLength);
     if (drawMode.testFlag(JKQTPCADMTickLabels)) {
@@ -2269,12 +2279,12 @@ void JKQTPHorizontalAxis::drawAxisLabel1(JKQTPEnhancedPainter &painter, double l
     }
 }
 
-void JKQTPHorizontalAxis::drawAxisLabel2(JKQTPEnhancedPainter &painter, double left, double top, QSizeF labelMax, JKQTPCADrawMode drawMode) {
+void JKQTPHorizontalAxisBase::drawAxisLabel2(JKQTPEnhancedPainter &painter, double left, double top, QSizeF labelMax, JKQTPCADrawMode drawMode) {
     double labelOffset=parent->pt2px(painter, axisStyle.labelDistance);
     if (drawMode.testFlag(JKQTPCADMTicks)) labelOffset+=parent->pt2px(painter, axisStyle.tickOutsideLength);
     if (drawMode.testFlag(JKQTPCADMTickLabels)) {
         labelOffset+=parent->pt2px(painter, axisStyle.tickLabelDistance);
-        labelOffset+=labelMax.width();//+labelMax.height();
+        labelOffset+=labelMax.height();//+labelMax.height();
     }
 
 
@@ -2314,7 +2324,7 @@ void JKQTPHorizontalAxis::drawAxisLabel2(JKQTPEnhancedPainter &painter, double l
     //painter.resetTransform();
 }
 
-void JKQTPHorizontalAxis::drawAxes(JKQTPEnhancedPainter& painter) {
+void JKQTPHorizontalAxisBase::drawAxes(JKQTPEnhancedPainter& painter, int move1, int move2) {
 #ifdef JKQTBP_AUTOTIMER
     JKQTPAutoOutputTimer jkaat(QString("JKQTPHorizontalAxis[%1]::drawAxes()").arg(objectName()));
 #endif
@@ -2338,8 +2348,8 @@ void JKQTPHorizontalAxis::drawAxes(JKQTPEnhancedPainter& painter) {
         bottom=getParentOtheraxisOffset()+getParentOtheraxisWidth();//;
     }
     // move axes outside plot rectangle, if required
-    top-=parent->pt2px(painter, axisStyle.axisLineOffset);
+    top-=parent->pt2px(painter, axisStyle.axisLineOffset)+move2;
-    bottom+=parent->pt2px(painter, axisStyle.axisLineOffset);
+    bottom+=parent->pt2px(painter, axisStyle.axisLineOffset)+move1;
 
     double ticklabelOffset1PT=axisStyle.tickLabelDistance; // offset of tick labels from axis 1
     double minorticklabelOffset1PT=axisStyle.tickLabelDistance; // offset ofminor tick labels from axis 1
@@ -2584,6 +2594,53 @@ void JKQTPHorizontalAxis::drawAxes(JKQTPEnhancedPainter& painter) {
 
 
 
+JKQTPHorizontalAxis::JKQTPHorizontalAxis(JKQTBasePlotter* parent, JKQTPCoordinateAxisRef otherAxisRef_):
+    JKQTPHorizontalAxisBase(parent), otherAxisRef(otherAxisRef_)
+{
+    //axisPrefix="xaxis_";
+    scaleSign=1;
+    if (parent) {
+        axisStyle=parent->getCurrentPlotterStyle().xAxisStyle;
+    } else {
+        axisStyle=JKQTPGetSystemDefaultBaseStyle().xAxisStyle;
+    }
+
+}
+
+double JKQTPHorizontalAxis::getParentPlotWidth() const {
+    return parent->getPlotWidth();
+}
+
+double JKQTPHorizontalAxis::getParentPlotOffset() const {
+    return parent->getInternalPlotBorderLeft();
+}
+
+double JKQTPHorizontalAxis::getParentOtheraxisOffset() const {
+    return getOtherAxis()->x2p(getOtherAxis()->getMax());
+}
+
+double JKQTPHorizontalAxis::parentOtherAxisX2P(double x) const
+{
+    return parent->y2p(x);
+}
+
+JKQTPCoordinateAxisRef JKQTPHorizontalAxis::getOtherAxisRef() const
+{
+    return otherAxisRef;
+}
+
+const JKQTPCoordinateAxis *JKQTPHorizontalAxis::getOtherAxis() const {
+    return parent->getYAxis(otherAxisRef);
+}
+
+double JKQTPHorizontalAxis::getParentOtheraxisWidth() const {
+    return fabs(getOtherAxis()->x2p(getOtherAxis()->getMax())-getOtherAxis()->x2p(getOtherAxis()->getMin()));
+}
+
+bool JKQTPHorizontalAxis::getParentOtheraxisInverted() const
+{
+    return getOtherAxis()->getInverted();
+}
 
 
 

lib/jkqtplotter/jkqtpcoordinateaxes.h

@@ -36,6 +36,19 @@
 // forward declarations
 class JKQTBasePlotter;
 
+/*! \brief named references for different oordinate axes in the plot
+    \ingroup jkqtpplottersupprt
+*/
+enum JKQTPCoordinateAxes: uint8_t {
+    JKQTPPrimaryAxis=0,
+    JKQTPSecondaryAxis=1
+};
+
+/*! \brief type for indexing coordinate axes in a plot
+    \ingroup jkqtpplottersupprt
+*/
+typedef JKQTPCoordinateAxes JKQTPCoordinateAxisRef;
+
 /*! \brief this virtual class is the base for any type of coordinate axis, to be drawn by JKQTBasePlotter.
     \ingroup jkqtpbaseplotter_elements
 
@@ -238,8 +251,13 @@ class JKQTPLOTTER_LIB_EXPORT JKQTPCoordinateAxis: public QObject {
         /** \brief returns the size of the right/top axis in pixels */
         virtual QSizeF getSize2(JKQTPEnhancedPainter& painter)=0;
 
-        /** \brief draw axes  */
+        /** \brief draw the axes
-        virtual void drawAxes(JKQTPEnhancedPainter& painter)=0;
+         *
+         *  \param painter the painter to use for drawing
+         *  \param move1 offset in pixels on the major side (horizontal: bottom, vertical: left)
+         *  \param move2 offset in pixels on the secondary side (horizontal: top, vertical: right)
+         */
+        virtual void drawAxes(JKQTPEnhancedPainter& painter, int move1=0, int move2=0)=0;
 
         /** \brief draw grids  */
         virtual void drawGrids(JKQTPEnhancedPainter& painter)=0;
@@ -650,6 +668,8 @@ class JKQTPLOTTER_LIB_EXPORT JKQTPCoordinateAxis: public QObject {
         void setTickColor(QColor c);
         /** \copydoc JKQTPCoordinateAxisStyle::tickLabelColor */
         void setTickLabelColor(QColor c) ;
+        /** \brief sets all colors (line, ticks, label, ...) of the axis */
+        void setColor(QColor c) ;
 
     protected:
         /** \brief returns the size of the zero axis in pixels, the first part of the return-value is the lhs size and the second part the rhs size */
@@ -852,20 +872,32 @@ class JKQTPLOTTER_LIB_EXPORT JKQTPCoordinateAxis: public QObject {
 
 
 
-/*! \brief implements a vertical axis, based on JKQTPCoordinateAxis (for most of documentation: see JKQTPCoordinateAxis).
+/*! \brief base class for vertical axes, based on JKQTPCoordinateAxis (for most of documentation: see JKQTPCoordinateAxis).
     \ingroup jkqtpbaseplotter_elements
 
-    The positioning of the different axis elements depends on the psition of the "other" axis (here x-axis),
+    The positioning of the different axis elements depends on the psition of the "other" axis (i.e. a horizontal/x-axis),
     i.e. the corresponding vertical axis:
 
-    \image html JKQTPHorizontalAxisPositioning.png
+    \image html JKQTPVerticalAxisPositioning.png
+
+    But this "other>" axis is not defined here, but has to be defined in derived classes by immplementing the corresponding
+    pure virtual functions:
+      - getParentPlotWidth()
+      - getParentPlotOffset()
+      - getParentOtheraxisWidth()
+      - getParentOtheraxisInverted()
+      - getParentOtheraxisOffset()
+      - parentOtherAxisX2P()
+    .
+
+    \see JKQTPHorizontalAxisBase
  */
-class JKQTPLOTTER_LIB_EXPORT JKQTPVerticalAxis: public JKQTPCoordinateAxis {
+class JKQTPLOTTER_LIB_EXPORT JKQTPVerticalAxisBase: public JKQTPCoordinateAxis {
         Q_OBJECT
     protected:
     public:
         /** \brief class constructor */
-        JKQTPVerticalAxis(JKQTBasePlotter* parent);
+        JKQTPVerticalAxisBase(JKQTBasePlotter* parent);
 
         /** \brief returns the size of the left axis in pixels */
         virtual QSizeF getSize1(JKQTPEnhancedPainter& painter) override;
@@ -874,25 +906,12 @@ class JKQTPLOTTER_LIB_EXPORT JKQTPVerticalAxis: public JKQTPCoordinateAxis {
         virtual QSizeF getSize2(JKQTPEnhancedPainter& painter) override;
 
         /** copydoc JKQTPCoordinateAxis::drawAxes() */
-        virtual void drawAxes(JKQTPEnhancedPainter& painter) override;
+        virtual void drawAxes(JKQTPEnhancedPainter& painter, int move1=0, int move2=0) override;
 
         /** copydoc JKQTPCoordinateAxis::drawGrids() */
         virtual void drawGrids(JKQTPEnhancedPainter& painter) override;
 
 
-        /** copydoc JKQTPCoordinateAxis::getParentPlotWidth() */
-        virtual double getParentPlotWidth() const override;
-        /** copydoc JKQTPCoordinateAxis::getParentPlotOffset() */
-        virtual double getParentPlotOffset() const override;
-        /** copydoc JKQTPCoordinateAxis::getParentOtheraxisWidth() */
-        virtual double getParentOtheraxisWidth() const override;
-        /** copydoc JKQTPCoordinateAxis::getParentOtheraxisInverted() */
-        virtual bool getParentOtheraxisInverted() const override;
-        /** copydoc JKQTPCoordinateAxis::getParentOtheraxisOffset() */
-        virtual double getParentOtheraxisOffset() const override;
-        /** copydoc JKQTPCoordinateAxis::parentOtherAxisX2P() */
-        virtual double parentOtherAxisX2P(double x) const override;
-
     protected:
         /** copydoc JKQTPCoordinateAxis::getSize0() */
         virtual std::pair<QSizeF,QSizeF> getSize0(JKQTPEnhancedPainter& painter) override;
@@ -922,6 +941,49 @@ class JKQTPLOTTER_LIB_EXPORT JKQTPVerticalAxis: public JKQTPCoordinateAxis {
         void drawAxisLabel1(JKQTPEnhancedPainter &painter, double left, double bottom, QSizeF labelMax, JKQTPCADrawMode drawMode);
         /** \brief draw the axis label using \a painter for axis 2 at \c x= \a right and \c y= \a bottom. \a labelMax is the maximum Size of all tick labels */
         void drawAxisLabel2(JKQTPEnhancedPainter &painter, double right, double bottom, QSizeF labelMax, JKQTPCADrawMode drawMode);
+
+};
+
+
+
+/*! \brief implements a vertical axis for use as primary, secondary, ... axis of a JKQTPBasePlotter,
+ *         based on JKQTPCoordinateAxis (for most of documentation: see JKQTPCoordinateAxis).
+    \ingroup jkqtpbaseplotter_elements
+
+    The positioning of the different axis elements depends on the psition of the "other" axis (here x-axis),
+    i.e. the corresponding vertical axis:
+
+    \image html JKQTPVerticalAxisPositioning.png
+ */
+class JKQTPLOTTER_LIB_EXPORT JKQTPVerticalAxis: public JKQTPVerticalAxisBase {
+        Q_OBJECT
+    protected:
+    public:
+        /** \brief class constructor */
+        JKQTPVerticalAxis(JKQTBasePlotter* parent, JKQTPCoordinateAxisRef otherAxisRef=JKQTPPrimaryAxis);
+
+
+        /** copydoc JKQTPCoordinateAxis::getParentPlotWidth() */
+        virtual double getParentPlotWidth() const override;
+        /** copydoc JKQTPCoordinateAxis::getParentPlotOffset() */
+        virtual double getParentPlotOffset() const override;
+        /** copydoc JKQTPCoordinateAxis::getParentOtheraxisWidth() */
+        virtual double getParentOtheraxisWidth() const override;
+        /** copydoc JKQTPCoordinateAxis::getParentOtheraxisInverted() */
+        virtual bool getParentOtheraxisInverted() const override;
+        /** copydoc JKQTPCoordinateAxis::getParentOtheraxisOffset() */
+        virtual double getParentOtheraxisOffset() const override;
+        /** copydoc JKQTPCoordinateAxis::parentOtherAxisX2P() */
+        virtual double parentOtherAxisX2P(double x) const override;
+        /** \copydoc otherAxisRef */
+        JKQTPCoordinateAxisRef getOtherAxisRef() const;
+        /** \brief returns the "other" axis, refernced by otherAxisRef */
+        const JKQTPCoordinateAxis* getOtherAxis() const;
+
+    protected:
+
+        /** \brief references the other axis fromm the JKQTPBasePLotter to use as "other" axis */
+        JKQTPCoordinateAxisRef otherAxisRef;
 };
 
 
@@ -944,7 +1006,7 @@ class JKQTPLOTTER_LIB_EXPORT JKQTPVerticalAxis: public JKQTPCoordinateAxis {
     If it is paired with another axis, the parameters of that axis have to be given explizitly in the constructor or with  setters.
 
  */
-class JKQTPLOTTER_LIB_EXPORT JKQTPVerticalIndependentAxis: public JKQTPVerticalAxis {
+class JKQTPLOTTER_LIB_EXPORT JKQTPVerticalIndependentAxis: public JKQTPVerticalAxisBase {
         Q_OBJECT
     protected:
     public:
@@ -990,20 +1052,33 @@ class JKQTPLOTTER_LIB_EXPORT JKQTPVerticalIndependentAxis: public JKQTPVerticalA
 
 
 
-/*! \brief implements a horizontal axis, based on JKQTPCoordinateAxis (for most of documentation: see JKQTPCoordinateAxis).
+/*! \brief base class for horizontal axes, based on JKQTPCoordinateAxis (for most of documentation: see JKQTPCoordinateAxis).
     \ingroup jkqtpbaseplotter_elements
 
-    The positioning of the different axis elements depends on the psition of the "other"  axis (here y-axis),
+    The positioning of the different axis elements depends on the psition of the "other"  axis (i.e. a vertical/y-axis),
     i.e. the corresponding vertical axis:
 
     \image html JKQTPHorizontalAxisPositioning.png
+
+
+    But this "other>" axis is not defined here, but has to be defined in derived classes by immplementing the corresponding
+    pure virtual functions:
+      - getParentPlotWidth()
+      - getParentPlotOffset()
+      - getParentOtheraxisWidth()
+      - getParentOtheraxisInverted()
+      - getParentOtheraxisOffset()
+      - parentOtherAxisX2P()
+    .
+
+    \see JKQTPVerticalAxisBase
  */
-class JKQTPLOTTER_LIB_EXPORT JKQTPHorizontalAxis: public JKQTPCoordinateAxis {
+class JKQTPLOTTER_LIB_EXPORT JKQTPHorizontalAxisBase: public JKQTPCoordinateAxis {
         Q_OBJECT
     protected:
     public:
         /** \brief class constructor */
-        JKQTPHorizontalAxis(JKQTBasePlotter* parent);
+        JKQTPHorizontalAxisBase(JKQTBasePlotter* parent);
 
         /** \brief returns the size of the bottom axis in pixels */
         virtual QSizeF getSize1(JKQTPEnhancedPainter& painter) override;
@@ -1012,25 +1087,12 @@ class JKQTPLOTTER_LIB_EXPORT JKQTPHorizontalAxis: public JKQTPCoordinateAxis {
         virtual QSizeF getSize2(JKQTPEnhancedPainter& painter) override;
 
         /** copydoc JKQTPCoordinateAxis::drawAxes() */
-        virtual void drawAxes(JKQTPEnhancedPainter& painter) override;
+        virtual void drawAxes(JKQTPEnhancedPainter& painter, int move1=0, int move2=0) override;
 
         /** copydoc JKQTPCoordinateAxis::drawGrids() */
         virtual void drawGrids(JKQTPEnhancedPainter& painter) override;
 
 
-        /** copydoc JKQTPCoordinateAxis::getParentPlotWidth() */
-        virtual double getParentPlotWidth() const override;
-        /** copydoc JKQTPCoordinateAxis::getParentPlotOffset() */
-        virtual double getParentPlotOffset() const override;
-        /** copydoc JKQTPCoordinateAxis::getParentOtheraxisWidth() */
-        virtual double getParentOtheraxisWidth() const override;
-        /** copydoc JKQTPCoordinateAxis::getParentOtheraxisInverted() */
-        virtual bool getParentOtheraxisInverted() const override;
-        /** copydoc JKQTPCoordinateAxis::getParentOtheraxisOffset() */
-        virtual double getParentOtheraxisOffset() const override;
-        /** copydoc JKQTPCoordinateAxis::parentOtherAxisX2P() */
-        virtual double parentOtherAxisX2P(double x) const override;
-
     protected:
         /** copydoc JKQTPCoordinateAxis::getSize0() */
         virtual std::pair<QSizeF, QSizeF> getSize0(JKQTPEnhancedPainter& painter) override;
@@ -1068,6 +1130,45 @@ class JKQTPLOTTER_LIB_EXPORT JKQTPHorizontalAxis: public JKQTPCoordinateAxis {
 };
 
 
+/*! \brief implements a horizontal axis, based on JKQTPCoordinateAxis (for most of documentation: see JKQTPCoordinateAxis).
+    \ingroup jkqtpbaseplotter_elements
+
+    The positioning of the different axis elements depends on the psition of the "other"  axis (here y-axis),
+    i.e. the corresponding vertical axis:
+
+    \image html JKQTPHorizontalAxisPositioning.png
+ */
+class JKQTPLOTTER_LIB_EXPORT JKQTPHorizontalAxis: public JKQTPHorizontalAxisBase {
+        Q_OBJECT
+    protected:
+    public:
+        /** \brief class constructor */
+        JKQTPHorizontalAxis(JKQTBasePlotter* parent, JKQTPCoordinateAxisRef otherAxisRef_=JKQTPPrimaryAxis);
+
+        /** copydoc JKQTPCoordinateAxis::getParentPlotWidth() */
+        virtual double getParentPlotWidth() const override;
+        /** copydoc JKQTPCoordinateAxis::getParentPlotOffset() */
+        virtual double getParentPlotOffset() const override;
+        /** copydoc JKQTPCoordinateAxis::getParentOtheraxisWidth() */
+        virtual double getParentOtheraxisWidth() const override;
+        /** copydoc JKQTPCoordinateAxis::getParentOtheraxisInverted() */
+        virtual bool getParentOtheraxisInverted() const override;
+        /** copydoc JKQTPCoordinateAxis::getParentOtheraxisOffset() */
+        virtual double getParentOtheraxisOffset() const override;
+        /** copydoc JKQTPCoordinateAxis::parentOtherAxisX2P() */
+        virtual double parentOtherAxisX2P(double x) const override;
+        /** \copydoc otherAxisRef */
+        JKQTPCoordinateAxisRef getOtherAxisRef() const;
+        /** \brief returns the "other" axis, refernced by otherAxisRef */
+        const JKQTPCoordinateAxis* getOtherAxis() const;
+
+    protected:
+
+        /** \brief references the other axis fromm the JKQTPBasePLotter to use as "other" axis */
+        JKQTPCoordinateAxisRef otherAxisRef;
+
+};
+
 /*! \brief implements a position-indipendent horizontal axis, based on JKQTPCoordinateAxis (for most of documentation: see JKQTPCoordinateAxis).
     \ingroup jkqtpbaseplotter_elements
 

lib/jkqtplotter/jkqtpgraphsbase.cpp

@@ -34,7 +34,7 @@
 #define SmallestGreaterZeroCompare_xvsgz() if ((xvsgz>10.0*DBL_MIN)&&((smallestGreaterZero<10.0*DBL_MIN) || (xvsgz<smallestGreaterZero))) smallestGreaterZero=xvsgz;
 
 JKQTPPlotElement::JKQTPPlotElement(JKQTBasePlotter* parent):
-    QObject(parent)
+    QObject(parent), xAxisRef(JKQTPPrimaryAxis), yAxisRef(JKQTPPrimaryAxis)
 {
     title="";
     visible=true;
@@ -225,18 +225,18 @@ double JKQTPPlotElement::hitTest(const QPointF & posSystem, QPointF* closestSpot
 }
 
 double JKQTPPlotElement::transformX(double x) const {
-    return parent->getXAxis()->x2p(x);
+    return getXAxis()->x2p(x);
 }
 
 double JKQTPPlotElement::transformY(double y) const {
-    return parent->getYAxis()->x2p(y);
+    return getYAxis()->x2p(y);
 }
 
 QVector<double> JKQTPPlotElement::transformX(const QVector<double>& x) const {
     QVector<double> res;
     res.resize(x.size());
     for (int i=0; i<x.size(); i++) {
-        res[i]=parent->getXAxis()->x2p(x[i]);
+        res[i]=getXAxis()->x2p(x[i]);
     }
     return res;
 }
@@ -245,18 +245,38 @@ QVector<double> JKQTPPlotElement::transformY(const QVector<double>& y) const {
     QVector<double> res;
     res.resize(y.size());
     for (int i=0; i<y.size(); i++) {
-        res[i]=parent->getYAxis()->x2p(y[i]);
+        res[i]=getYAxis()->x2p(y[i]);
     }
     return res;
 }
 
+void JKQTPPlotElement::setXAxis(JKQTPCoordinateAxisRef ref)
+{
+    xAxisRef=ref;
+}
+
+void JKQTPPlotElement::setYAxis(JKQTPCoordinateAxisRef ref)
+{
+    yAxisRef=ref;
+}
+
+JKQTPCoordinateAxisRef JKQTPPlotElement::getXAxisRef() const
+{
+    return xAxisRef;
+}
+
+JKQTPCoordinateAxisRef JKQTPPlotElement::getYAxisRef() const
+{
+    return yAxisRef;
+}
+
 
 double JKQTPPlotElement::backtransformX(double x) const {
-    return parent->getXAxis()->p2x(x);
+    return getXAxis()->p2x(x);
 }
 
 double JKQTPPlotElement::backtransformY(double y) const {
-    return parent->getYAxis()->p2x(y);
+    return getYAxis()->p2x(y);
 }
 
 

lib/jkqtplotter/jkqtpgraphsbase.h

@@ -208,16 +208,16 @@ class JKQTPLOTTER_LIB_EXPORT JKQTPPlotElement: public QObject {
 
 
 
-        /** \brief tool routine that transforms an x-coordinate (plot coordinate --> pixels) for this plot element */
+        /** \brief tool routine that transforms an x-coordinate (plot coordinate --> pixels) for this plot element, uses the axis referenced in xAxisRef */
         double transformX(double x) const;
 
-        /** \brief tool routine that transforms a y-coordinate (plot coordinate --> pixels) for this plot element */
+        /** \brief tool routine that transforms a y-coordinate (plot coordinate --> pixels) for this plot element, uses the axis referenced in yAxisRef */
         double transformY(double y) const;
 
-        /** \brief tool routine that backtransforms an x-coordinate (pixels --> plot coordinate) for this plot element */
+        /** \brief tool routine that backtransforms an x-coordinate (pixels --> plot coordinate) for this plot element, uses the axis referenced in xAxisRef */
         double backtransformX(double x) const;
 
-        /** \brief tool routine that backtransforms a y-coordinate (pixels --> plot coordinate) for this plot element */
+        /** \brief tool routine that backtransforms a y-coordinate (pixels --> plot coordinate) for this plot element, uses the axis referenced in yAxisRef */
         double backtransformY(double y) const;
 
 
@@ -254,6 +254,31 @@ class JKQTPLOTTER_LIB_EXPORT JKQTPPlotElement: public QObject {
         /** \brief transform all y-coordinates in a vector \a x */
         QVector<double> transformY(const QVector<double>& x) const;
 
+        /** \copydoc xAxisRef */
+        void setXAxis(JKQTPCoordinateAxisRef ref);
+        /** \copydoc xAxisRef */
+        JKQTPCoordinateAxisRef getXAxisRef() const;
+        /** \copydoc yAxisRef */
+        void setYAxis(JKQTPCoordinateAxisRef ref);
+        /** \copydoc yAxisRef */
+        JKQTPCoordinateAxisRef getYAxisRef() const;
+        /** \brief returns the actual x-Axis-object from the parent plotter, referenced in xAxisRef */
+        /** \brief returns the actual x-Axis-object from the parent plotter, referenced in xAxisRef */
+        inline const JKQTPCoordinateAxis* getXAxis() const {
+            return parent->getXAxis(xAxisRef);
+        }
+        /** \brief returns the actual y-Axis-object from the parent plotter, referenced in yAxisRef */
+        inline const JKQTPCoordinateAxis* getYAxis() const {
+            return parent->getYAxis(yAxisRef);
+        }
+        /** \brief set the coordinate axes to use for this plot element
+         *
+         *  \see xAxisRef, yAxisRef, transformX(), transformY()
+         */
+        void setAxes(JKQTPCoordinateAxisRef ref);
+
+        Q_PROPERTY(JKQTPCoordinateAxisRef xAxisRef READ getXAxisRef WRITE setXAxis)
+        Q_PROPERTY(JKQTPCoordinateAxisRef yAxisRef READ getYAxisRef WRITE setYAxis)
 
     protected:
 
@@ -356,6 +381,11 @@ class JKQTPLOTTER_LIB_EXPORT JKQTPPlotElement: public QObject {
         bool highlighted;
         /** \brief internal storage for the used parent plot style */
         int parentPlotStyle;
+        /** \brief indicates which coordinate axis to use for coordinate transforms in x-direction */
+        JKQTPCoordinateAxisRef xAxisRef;
+        /** \brief indicates which coordinate axis to use for coordinate transforms in y-direction */
+        JKQTPCoordinateAxisRef yAxisRef;
+
 
 
         /** \brief dataset with graph-points and associated data fro the function hitTest()

lib/jkqtplotter/jkqtpgraphsbaseerrors.cpp

@@ -272,10 +272,10 @@ void JKQTPGraphErrorStyleMixin::intPlotXYErrorIndicators(JKQTPEnhancedPainter& p
     if (!visX&&!visY) return;
     //std::cout<<"   JKQTPGraphErrors::intPlotXYErrorIndicators(p, "<<parent<<", "<<xColumn<<", "<<yColumn<<", "<<xErrorColumn<<", "<<yErrorColumn<<", ...)\n";
 
-    const double xmin=parentGraph->transformX(parent->getXAxis()->getMin());
+    const double xmin=parentGraph->transformX(parentGraph->getXAxis()->getMin());
-    const double xmax=parentGraph->transformX(parent->getXAxis()->getMax());
+    const double xmax=parentGraph->transformX(parentGraph->getXAxis()->getMax());
-    const double ymin=parentGraph->transformY(parent->getYAxis()->getMin());
+    const double ymin=parentGraph->transformY(parentGraph->getYAxis()->getMin());
-    const double ymax=parentGraph->transformY(parent->getYAxis()->getMax());
+    const double ymax=parentGraph->transformY(parentGraph->getYAxis()->getMax());
     const QMarginsF clipMargins(50,50,50,50);
     const QRectF cliprect=QRectF(qMin(xmin,xmax),qMin(ymin,ymax),fabs(xmax-xmin),fabs(ymax-ymin))+clipMargins;
 

lib/jkqtplotter/jkqtplotter.cpp

@@ -796,7 +796,7 @@ void JKQTPlotter::mouseMoveEvent ( QMouseEvent * event ) {
                 } else {
                     zoomRect.translate(mouseDragRectXStartPixel-mouseDragRectXEndPixel, mouseDragRectYStartPixel-mouseDragRectYEndPixel);
                 }
-                setXY(plotter->p2x(zoomRect.left()), plotter->p2x(zoomRect.right()), plotter->p2y(zoomRect.bottom()), plotter->p2y(zoomRect.top()));
+                setXY(plotter->p2x(zoomRect.left()), plotter->p2x(zoomRect.right()), plotter->p2y(zoomRect.bottom()), plotter->p2y(zoomRect.top()), true);
             }
 
         } else {
@@ -900,7 +900,7 @@ void JKQTPlotter::mouseReleaseEvent ( QMouseEvent * event ){
                 plotter->correctXYRangeForAspectRatio(xmin,xmax,ymin,ymax);
 
                 emit zoomChangedLocally(xmin, xmax, ymin, ymax, this);
-                plotter->setXY(xmin, xmax, ymin, ymax);
+                plotter->setXY(xmin, xmax, ymin, ymax, true);
             } else if (currentMouseDragAction.mode==jkqtpmdaPanPlotOnRelease) {
                 QRectF zoomRect= QRectF(QPointF(plotter->x2p(getXAxis()->getMin()),plotter->y2p(getYAxis()->getMax())), QPointF(plotter->x2p(getXAxis()->getMax()),plotter->y2p(getYAxis()->getMin())));
                 if  ( (mouseLastClickX/magnification<plotter->getInternalPlotBorderLeft()) || (mouseLastClickX/magnification>plotter->getPlotWidth()+plotter->getInternalPlotBorderLeft()) ) {
@@ -910,7 +910,7 @@ void JKQTPlotter::mouseReleaseEvent ( QMouseEvent * event ){
                 } else {
                     zoomRect.translate(mouseDragRectXStartPixel-mouseDragRectXEndPixel, mouseDragRectYStartPixel-mouseDragRectYEndPixel);
                 }
-                setXY(plotter->p2x(zoomRect.left()), plotter->p2x(zoomRect.right()), plotter->p2y(zoomRect.bottom()), plotter->p2y(zoomRect.top()));
+                setXY(plotter->p2x(zoomRect.left()), plotter->p2x(zoomRect.right()), plotter->p2y(zoomRect.bottom()), plotter->p2y(zoomRect.top()), true);
             } else if (currentMouseDragAction.mode==jkqtpmdaDrawRectangleForEvent) {
                 emit userRectangleFinished(x1, y1, x2-x1, y2-y1, event->modifiers());
             } else if (currentMouseDragAction.mode==jkqtpmdaDrawCircleForEvent) {
@@ -962,7 +962,7 @@ void JKQTPlotter::mouseDoubleClickEvent ( QMouseEvent * event ){
                 ymin=getYMin();
                 ymax=getYMax();
             }
-            plotter->setXY(xmin, xmax, ymin, ymax);
+            plotter->setXY(xmin, xmax, ymin, ymax, true);
             update();
         } else if (itAction.value()==JKQTPMouseDoubleClickActions::jkqtpdcaClickMovesViewport) {
             QRectF zoomRect= QRectF(QPointF(plotter->x2p(getXAxis()->getMin()),plotter->y2p(getYAxis()->getMax())), QPointF(plotter->x2p(getXAxis()->getMax()),plotter->y2p(getYAxis()->getMin())));
@@ -973,7 +973,7 @@ void JKQTPlotter::mouseDoubleClickEvent ( QMouseEvent * event ){
             } else {
                 zoomRect.moveCenter(QPointF(event->pos().x(), event->pos().y()));
             }
-            setXY(plotter->p2x(zoomRect.left()), plotter->p2x(zoomRect.right()), plotter->p2y(zoomRect.bottom()), plotter->p2y(zoomRect.top()));
+            setXY(plotter->p2x(zoomRect.left()), plotter->p2x(zoomRect.right()), plotter->p2y(zoomRect.bottom()), plotter->p2y(zoomRect.top()), true);
         }
     }
 
@@ -1037,7 +1037,7 @@ void JKQTPlotter::wheelEvent ( QWheelEvent * event ) {
                 ymin=getYMin();
                 ymax=getYMax();
             }
-            plotter->setXY(xmin, xmax, ymin, ymax);
+            plotter->setXY(xmin, xmax, ymin, ymax, true);
         } else if (itAction.value()==JKQTPMouseWheelActions::jkqtpmwaPanByWheel) {
         //} else if (act==JKQTPMouseWheelActions::jkqtpmwaPanByWheel) {
             //qDebug()<<"wheelEvent("<<event->modifiers()<<"):PanByWheel";
@@ -1059,7 +1059,7 @@ void JKQTPlotter::wheelEvent ( QWheelEvent * event ) {
             } else {
                 zoomRect.translate(d.x(), d.y());
             }
-            setXY(plotter->p2x(zoomRect.left()), plotter->p2x(zoomRect.right()), plotter->p2y(zoomRect.bottom()), plotter->p2y(zoomRect.top()));
+            setXY(plotter->p2x(zoomRect.left()), plotter->p2x(zoomRect.right()), plotter->p2y(zoomRect.bottom()), plotter->p2y(zoomRect.top()), true);
         }
     }
 

lib/jkqtplotter/jkqtplotter.h

@@ -697,13 +697,13 @@ class JKQTPLOTTER_LIB_EXPORT JKQTPlotter: public QWidget {
         int getMouseLastClickY() const;
 
         /** \brief returns the coordinate axis object for the x-axis \see JKQTBasePlotter::getXAxis() */
-        inline JKQTPHorizontalAxis* getXAxis() { return plotter->getXAxis(); }
+        inline JKQTPHorizontalAxisBase* getXAxis(JKQTPCoordinateAxisRef axis=JKQTPPrimaryAxis) { return plotter->getXAxis(axis); }
         /** \brief returns the coordinate axis object for the y-axis \see JKQTBasePlotter::getYAxis()  */
-        inline JKQTPVerticalAxis* getYAxis() { return plotter->getYAxis(); }
+        inline JKQTPVerticalAxisBase* getYAxis(JKQTPCoordinateAxisRef axis=JKQTPPrimaryAxis) { return plotter->getYAxis(axis); }
         /** \brief returns the coordinate axis object for the x-axis as a const pointer \see JKQTBasePlotter::getXAxis()  */
-        inline const JKQTPHorizontalAxis* getXAxis() const { return plotter->getXAxis(); }
+        inline const JKQTPHorizontalAxisBase* getXAxis(JKQTPCoordinateAxisRef axis=JKQTPPrimaryAxis) const { return plotter->getXAxis(axis); }
         /** \brief returns the coordinate axis object for the y-axis as a const pointer \see JKQTBasePlotter::getYAxis()  */
-        inline const JKQTPVerticalAxis* getYAxis() const { return plotter->getYAxis(); }
+        inline const JKQTPVerticalAxisBase* getYAxis(JKQTPCoordinateAxisRef axis=JKQTPPrimaryAxis) const { return plotter->getYAxis(axis); }
 
        /** \brief returns the \a i -th graph (of type JKQTPPlotElement) in this plotter instance \see JKQTBasePlotter::getGraph() */
         inline JKQTPPlotElement* getGraph(size_t i) { return plotter->getGraph(i); }
@@ -1185,6 +1185,10 @@ class JKQTPLOTTER_LIB_EXPORT JKQTPlotter: public QWidget {
          *  \param xmaxx absolute maximum of x-axis
          *  \param yminn absolute minimum of y-axis
          *  \param ymaxx absolute maximum of y-axis
+         *  \param affectsSecondaryAxes if \c true, the secondary axes are affectedtoo, by using a relative zooming scheme,
+         *                              i.e. if a major axis range shrinks by 50%, also the secondary ranges shrink by 50%
+         *                              [default: \c false]
+         *
          *
          * \note You cannot expand the ranges outside the absolute ranges set e.g. by setAbsoluteXY()!
          *       Also the range will be limited to possible values (e.g. to positive values if you use
@@ -1195,7 +1199,7 @@ class JKQTPLOTTER_LIB_EXPORT JKQTPlotter: public QWidget {
          *
          * \see setX(), setX(), zoomToFit(), setAbsoluteXY(), JKQTBasePlotter::setXY()
          */
-         inline void setXY(double xminn, double xmaxx, double yminn, double ymaxx) { plotter->setXY(xminn, xmaxx, yminn, ymaxx); }
+         inline void setXY(double xminn, double xmaxx, double yminn, double ymaxx, bool affectsSecondaryAxes=false) { plotter->setXY(xminn, xmaxx, yminn, ymaxx, affectsSecondaryAxes); }
     signals:
         /** \brief emitted whenever the mouse moves
          *