added example project for error indicator styles

README.md

@@ -22,6 +22,7 @@ All test-projects are Qt-projects that use qmake to build. You can load them int
 | [![](https://raw.githubusercontent.com/jkriege2/JKQtPlotter/master/screenshots/jkqtplotter_simpletest_logaxes_small.png)](https://github.com/jkriege2/JKQtPlotter/tree/master/test/jkqtplotter_simpletest_logaxes) | [logarithmic axes](https://github.com/jkriege2/JKQtPlotter/tree/master/test/jkqtplotter_simpletest_logaxes) | `JKQTPxyLineGraph` and `JKQTPgeoText`<br/>C++ vector of data<br/>logarithmic axes<br/>plot line styles<br/>internal LaTeX parser<br/>add commenting text to a graph |
 | [![](https://raw.githubusercontent.com/jkriege2/JKQtPlotter/master/screenshots/jkqtplotter_simpletest_dateaxes_small.png)<br>![](https://raw.githubusercontent.com/jkriege2/JKQtPlotter/master/screenshots/jkqtplotter_simpletest_dateaxes_dates_small.png)<br>![](https://raw.githubusercontent.com/jkriege2/JKQtPlotter/master/screenshots/jkqtplotter_simpletest_dateaxes_timeaxis_small.png)](https://github.com/jkriege2/JKQtPlotter/tree/master/test/jkqtplotter_simpletest_dateaxes) | [date/time axes](https://github.com/jkriege2/JKQtPlotter/tree/master/test/jkqtplotter_simpletest_dateaxes) | `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 |
 | [![](https://raw.githubusercontent.com/jkriege2/JKQtPlotter/master/screenshots/jkqtplotter_simpletest_symbols_and_errors_small.png)](https://github.com/jkriege2/JKQtPlotter/tree/master/test/jkqtplotter_simpletest_symbols_and_errors) | [Simple Line/Symbol Graph With Errorbars](https://github.com/jkriege2/JKQtPlotter/tree/master/test/jkqtplotter_simpletest_symbols_and_errors) | `JKQTPxyLineErrorGraph`<br/>C-style arrays of data |
+| [![](https://raw.githubusercontent.com/jkriege2/JKQtPlotter/master/screenshots/jkqtplotter_simpletest_errorbarstyles_small.png)](https://github.com/jkriege2/JKQtPlotter/tree/master/test/jkqtplotter_simpletest_errorbarstyles) | [Different Types of Errorindicators](https://github.com/jkriege2/JKQtPlotter/tree/master/test/jkqtplotter_simpletest_errorbarstyles) | `JKQTPxyLineErrorGraph`<br/>different styles of error indicators for x- and y-errors<br>C++-style QVector for data<br/>styling error indicators<br/>moving key and formatting plotter grid |
 | [![](https://raw.githubusercontent.com/jkriege2/JKQtPlotter/master/screenshots/jkqtplotter_simpletest_barchart_small.png)](https://github.com/jkriege2/JKQtPlotter/tree/master/test/jkqtplotter_simpletest_barchart) | [Simple Bar Charts](https://github.com/jkriege2/JKQtPlotter/tree/master/test/jkqtplotter_simpletest_barchart) | `JKQTPbarVerticalGraph`<br/>C-style arrays of data |
 | [![](https://raw.githubusercontent.com/jkriege2/JKQtPlotter/master/screenshots/JKQTPbarVerticalGraphStacked_small.png)<br>![](https://raw.githubusercontent.com/jkriege2/JKQtPlotter/master/screenshots/JKQTPbarHorizontalGraphStacked_small.png)](https://github.com/jkriege2/JKQtPlotter/tree/master/test/jkqtplotter_simpletest_stackedbars) | [Stacked Bar Charts](https://github.com/jkriege2/JKQtPlotter/tree/master/test/jkqtplotter_simpletest_stackedbars) | `JKQTPbarVerticalStackableGraph`, `JKQTPbarHorizontalStackableGraph`<br/>C++-style vectors of data |
 

lib/jkqtplotter/jkqtpbaseplotter.cpp

@@ -3158,13 +3158,13 @@ void JKQtBasePlotter::resetMasterSynchronization() {
 
 size_t JKQtBasePlotter::addGraph(size_t xColumn, size_t yColumn, QString title, JKQTPgraphPlotstyle graphStyle) {
     if (graphStyle==JKQTPimpulsesHorizontal) {
-        JKQTPimpulsesHorizontalGraph* gr=new JKQTPimpulsesHorizontalGraph(this);
+        JKQTPimpulsesVerticalGraph* gr=new JKQTPimpulsesVerticalGraph(this);
         gr->set_title(title);
         gr->set_xColumn(xColumn);
         gr->set_yColumn(yColumn);
         return addGraph(gr);
     } else if (graphStyle==JKQTPimpulsesVertical) {
-        JKQTPimpulsesVerticalGraph* gr=new JKQTPimpulsesVerticalGraph(this);
+        JKQTPimpulsesHorizontalGraph* gr=new JKQTPimpulsesHorizontalGraph(this);
         gr->set_title(title);
         gr->set_xColumn(xColumn);
         gr->set_yColumn(yColumn);
@@ -3207,7 +3207,7 @@ size_t JKQtBasePlotter::addGraph(size_t xColumn, size_t yColumn, QString title,
 
 size_t JKQtBasePlotter::addGraph(size_t xColumn, size_t yColumn, QString title, JKQTPgraphPlotstyle graphStyle, QColor color, JKQTPgraphSymbols symbol, Qt::PenStyle penstyle, double width) {
     if (graphStyle==JKQTPimpulsesHorizontal) {
-        JKQTPimpulsesHorizontalGraph* gr=new JKQTPimpulsesHorizontalGraph(this);
+        JKQTPimpulsesVerticalGraph* gr=new JKQTPimpulsesVerticalGraph(this);
         gr->set_title(title);
         gr->set_xColumn(xColumn);
         gr->set_yColumn(yColumn);
@@ -3215,7 +3215,7 @@ size_t JKQtBasePlotter::addGraph(size_t xColumn, size_t yColumn, QString title,
         gr->set_lineWidth(width);
         return addGraph(gr);
     } else if (graphStyle==JKQTPimpulsesVertical) {
-        JKQTPimpulsesVerticalGraph* gr=new JKQTPimpulsesVerticalGraph(this);
+        JKQTPimpulsesHorizontalGraph* gr=new JKQTPimpulsesHorizontalGraph(this);
         gr->set_title(title);
         gr->set_xColumn(xColumn);
         gr->set_yColumn(yColumn);

lib/jkqtplotter/jkqtpelements.cpp

@@ -526,7 +526,7 @@ void JKQTPxyLineErrorGraph::drawErrorsBefore(JKQTPEnhancedPainter &painter)
 
 
 
-JKQTPimpulsesHorizontalGraph::JKQTPimpulsesHorizontalGraph(JKQtBasePlotter* parent):
+JKQTPimpulsesVerticalGraph::JKQTPimpulsesVerticalGraph(JKQtBasePlotter* parent):
     JKQTPxyGraph(parent)
 {
     baseline=0;
@@ -540,7 +540,7 @@ JKQTPimpulsesHorizontalGraph::JKQTPimpulsesHorizontalGraph(JKQtBasePlotter* pare
     }
 }
 
-JKQTPimpulsesHorizontalGraph::JKQTPimpulsesHorizontalGraph(JKQtPlotter* parent):
+JKQTPimpulsesVerticalGraph::JKQTPimpulsesVerticalGraph(JKQtPlotter* parent):
     JKQTPxyGraph(parent)
 {
     baseline=0;
@@ -553,9 +553,9 @@ JKQTPimpulsesHorizontalGraph::JKQTPimpulsesHorizontalGraph(JKQtPlotter* parent):
         color=parent->getPlotStyle(parentPlotStyle).color();
     }
 }
-void JKQTPimpulsesHorizontalGraph::draw(JKQTPEnhancedPainter& painter) {
+void JKQTPimpulsesVerticalGraph::draw(JKQTPEnhancedPainter& painter) {
 #ifdef JKQTBP_AUTOTIMER
-    JKQTPAutoOutputTimer jkaaot("JKQTPimpulsesHorizontalGraph::draw");
+    JKQTPAutoOutputTimer jkaaot("JKQTPimpulsesVerticalGraph::draw");
 #endif
     if (parent==nullptr) return;
     JKQTPdatastore* datastore=parent->getDatastore();
@@ -627,7 +627,7 @@ void JKQTPimpulsesHorizontalGraph::draw(JKQTPEnhancedPainter& painter) {
     drawErrorsAfter(painter);
 }
 
-void JKQTPimpulsesHorizontalGraph::drawKeyMarker(JKQTPEnhancedPainter& painter, QRectF& rect) {
+void JKQTPimpulsesVerticalGraph::drawKeyMarker(JKQTPEnhancedPainter& painter, QRectF& rect) {
 
 
     painter.save();
@@ -642,7 +642,7 @@ void JKQTPimpulsesHorizontalGraph::drawKeyMarker(JKQTPEnhancedPainter& painter,
     painter.restore();
 }
 
-QColor JKQTPimpulsesHorizontalGraph::getKeyLabelColor() {
+QColor JKQTPimpulsesVerticalGraph::getKeyLabelColor() {
     return color;
 }
 
@@ -656,20 +656,20 @@ QColor JKQTPimpulsesHorizontalGraph::getKeyLabelColor() {
 
 
 
-JKQTPimpulsesVerticalGraph::JKQTPimpulsesVerticalGraph(JKQtBasePlotter* parent):
+JKQTPimpulsesHorizontalGraph::JKQTPimpulsesHorizontalGraph(JKQtBasePlotter* parent):
-    JKQTPimpulsesHorizontalGraph(parent)
+    JKQTPimpulsesVerticalGraph(parent)
 {
 }
 
-JKQTPimpulsesVerticalGraph::JKQTPimpulsesVerticalGraph(JKQtPlotter *parent):
+JKQTPimpulsesHorizontalGraph::JKQTPimpulsesHorizontalGraph(JKQtPlotter *parent):
-    JKQTPimpulsesHorizontalGraph(parent)
+    JKQTPimpulsesVerticalGraph(parent)
 {
 
 }
 
-void JKQTPimpulsesVerticalGraph::draw(JKQTPEnhancedPainter& painter) {
+void JKQTPimpulsesHorizontalGraph::draw(JKQTPEnhancedPainter& painter) {
 #ifdef JKQTBP_AUTOTIMER
-    JKQTPAutoOutputTimer jkaaot("JKQTPimpulsesVerticalGraph::draw");
+    JKQTPAutoOutputTimer jkaaot("JKQTPimpulsesHorizontalGraph::draw");
 #endif
     if (parent==nullptr) return;
     JKQTPdatastore* datastore=parent->getDatastore();
@@ -1805,7 +1805,7 @@ QBrush JKQTPxyLineGraph::getBrush(JKQTPEnhancedPainter& /*painter*/) const {
 }
 
 
-QPen JKQTPimpulsesHorizontalGraph::getPen(JKQTPEnhancedPainter& painter) const {
+QPen JKQTPimpulsesVerticalGraph::getPen(JKQTPEnhancedPainter& painter) const {
     QPen p;
     p.setColor(color);
     p.setWidthF(qMax(JKQTPLOTTER_ABS_MIN_LINEWIDTH,parent->pt2px(painter, parent->get_lineWidthMultiplier()*lineWidth)));
@@ -1870,7 +1870,7 @@ QPen JKQTPhorizontalRange::getLinePen(JKQTPEnhancedPainter& painter) const {
 
 bool JKQTPimpulsesHorizontalErrorGraph::usesColumn(int c)
 {
-    return JKQTPimpulsesHorizontalGraph::usesColumn(c)|| JKQTPxGraphErrors::errorUsesColumn(c);
+    return JKQTPimpulsesVerticalGraph::usesColumn(c)|| JKQTPxGraphErrors::errorUsesColumn(c);
 }
 
 void JKQTPimpulsesHorizontalErrorGraph::drawErrorsAfter(JKQTPEnhancedPainter &painter)
@@ -1880,20 +1880,20 @@ void JKQTPimpulsesHorizontalErrorGraph::drawErrorsAfter(JKQTPEnhancedPainter &pa
 }
 
 JKQTPimpulsesVerticalErrorGraph::JKQTPimpulsesVerticalErrorGraph(JKQtBasePlotter *parent):
-    JKQTPimpulsesVerticalGraph(parent), JKQTPyGraphErrors()
+    JKQTPimpulsesHorizontalGraph(parent), JKQTPyGraphErrors()
 {
     setErrorColorFromGraphColor(color);
 }
 
 JKQTPimpulsesVerticalErrorGraph::JKQTPimpulsesVerticalErrorGraph(JKQtPlotter *parent):
-    JKQTPimpulsesVerticalGraph(parent), JKQTPyGraphErrors()
+    JKQTPimpulsesHorizontalGraph(parent), JKQTPyGraphErrors()
 {
     setErrorColorFromGraphColor(color);
 }
 
 bool JKQTPimpulsesVerticalErrorGraph::usesColumn(int c)
 {
-    return JKQTPimpulsesVerticalGraph::usesColumn(c)|| JKQTPyGraphErrors::errorUsesColumn(c);
+    return JKQTPimpulsesHorizontalGraph::usesColumn(c)|| JKQTPyGraphErrors::errorUsesColumn(c);
 }
 
 void JKQTPimpulsesVerticalErrorGraph::drawErrorsAfter(JKQTPEnhancedPainter &painter)

lib/jkqtplotter/jkqtpelements.h

@@ -360,13 +360,13 @@ class LIB_EXPORT JKQTPxyParametrizedErrorScatterGraph: public JKQTPxyParametrize
 
     \image html plot_impulsesxplots.png
  */
-class LIB_EXPORT JKQTPimpulsesHorizontalGraph: public JKQTPxyGraph {
+class LIB_EXPORT JKQTPimpulsesVerticalGraph: public JKQTPxyGraph {
         Q_OBJECT
     public:
         /** \brief class constructor */
-        JKQTPimpulsesHorizontalGraph(JKQtBasePlotter* parent=nullptr);
+        JKQTPimpulsesVerticalGraph(JKQtBasePlotter* parent=nullptr);
         /** \brief class constructor */
-        JKQTPimpulsesHorizontalGraph(JKQtPlotter* parent);
+        JKQTPimpulsesVerticalGraph(JKQtPlotter* parent);
 
         /** \brief plots the graph to the plotter object specified as parent */
         virtual void draw(JKQTPEnhancedPainter& painter);
@@ -401,17 +401,17 @@ class LIB_EXPORT JKQTPimpulsesHorizontalGraph: public JKQTPxyGraph {
 
     \image html plot_impulsesxerrorsplots.png
  */
-class LIB_EXPORT JKQTPimpulsesHorizontalErrorGraph: public JKQTPimpulsesHorizontalGraph, public JKQTPxGraphErrors {
+class LIB_EXPORT JKQTPimpulsesHorizontalErrorGraph: public JKQTPimpulsesVerticalGraph, public JKQTPxGraphErrors {
         Q_OBJECT
     public:
         /** \brief class constructor */
         inline JKQTPimpulsesHorizontalErrorGraph(JKQtBasePlotter* parent=nullptr):
-            JKQTPimpulsesHorizontalGraph(parent), JKQTPxGraphErrors()
+            JKQTPimpulsesVerticalGraph(parent), JKQTPxGraphErrors()
         {
             setErrorColorFromGraphColor(color);
         }
         inline JKQTPimpulsesHorizontalErrorGraph(JKQtPlotter* parent):
-            JKQTPimpulsesHorizontalGraph(parent), JKQTPxGraphErrors()
+            JKQTPimpulsesVerticalGraph(parent), JKQTPxGraphErrors()
         {
             setErrorColorFromGraphColor(color);
         }
@@ -432,13 +432,13 @@ class LIB_EXPORT JKQTPimpulsesHorizontalErrorGraph: public JKQTPimpulsesHorizont
 
     \image html plot_impulsesyplots.png
  */
-class LIB_EXPORT JKQTPimpulsesVerticalGraph: public JKQTPimpulsesHorizontalGraph {
+class LIB_EXPORT JKQTPimpulsesHorizontalGraph: public JKQTPimpulsesVerticalGraph {
         Q_OBJECT
     public:
         /** \brief class constructor */
-        JKQTPimpulsesVerticalGraph(JKQtBasePlotter* parent=nullptr);
+        JKQTPimpulsesHorizontalGraph(JKQtBasePlotter* parent=nullptr);
         /** \brief class constructor */
-        JKQTPimpulsesVerticalGraph(JKQtPlotter* parent);
+        JKQTPimpulsesHorizontalGraph(JKQtPlotter* parent);
 
         /** \brief plots the graph to the plotter object specified as parent */
         virtual void draw(JKQTPEnhancedPainter& painter);
@@ -451,7 +451,7 @@ class LIB_EXPORT JKQTPimpulsesVerticalGraph: public JKQTPimpulsesHorizontalGraph
 
     \image html plot_impulsesyerrorsplots.png
  */
-class LIB_EXPORT JKQTPimpulsesVerticalErrorGraph: public JKQTPimpulsesVerticalGraph, public JKQTPyGraphErrors {
+class LIB_EXPORT JKQTPimpulsesVerticalErrorGraph: public JKQTPimpulsesHorizontalGraph, public JKQTPyGraphErrors {
         Q_OBJECT
     public:
         /** \brief class constructor */

test/jkqtplotter_simpletest_errorbarstyles/README.md

@@ -0,0 +1,120 @@
+[Back to JKQTPlotter main page](https://github.com/jkriege2/JKQtPlotter/)
+
+# JKQtPlotter
+
+## Different Types of Errorindicators
+This project (see `./test/jkqtplotter_simpletest_errorbarstyles/`) simply creates a JKQtPlotter widget (as a new window) and adds several curves show-casing different styles of error indicators. Data is initialized from two QVector<double> objects.
+
+The source code of the main application can be found in  [`jkqtplotter_simpletest_errorbarstyles.cpp`](https://github.com/jkriege2/JKQtPlotter/blob/master/test/jkqtplotter_simpletest_errorbarstyles/jkqtplotter_simpletest_errorbarstyles.cpp). 
+
+First some data is added to the internal datastore (mostly, like explained in several other examples, like e.g. [Line Graph with Different Symbols and Line Styles](https://github.com/jkriege2/JKQtPlotter/tree/master/test/jkqtplotter_simpletest_symbols_and_styles)). The (in a loop) several graphs are added, each with a distinct style for its error indicators:
+
+```c++
+    // 3. now we make several plots with different error styles
+    //    for that we iterate over every style from the vector errorStyles
+    //    the array showXandYError indicates whether we want x- and y-error
+    //    for a style for all stywhere this is false, only y-error-indicators
+    //    are shown
+	QVector<JKQTPerrorPlotstyle> errorStyles    {JKQTPnoError, JKQTPerrorBars, JKQTPerrorSimpleBars, JKQTPerrorLines, JKQTPerrorPolygons, JKQTPerrorBoxes, JKQTPerrorEllipses, JKQTPerrorBarsPolygons, JKQTPerrorBarsLines, JKQTPerrorSimpleBarsLines, JKQTPerrorSimpleBarsPolygons };
+    QVector<bool>                showXandYError { false      , true          , true                , false          , false             , true           , true              , false                 , false              , false                    , false                        };
+
+    for (int errorID=0; errorID<errorStyles.size(); errorID++) {
+        // generate some plot data
+        QVector<double> Y;
+        for (auto& xx: X) {
+            Y<<xx*0.5+static_cast<double>(errorID)*2.5;
+        }
+
+		// create a graph object
+        JKQTPxyLineErrorGraph* graph=new JKQTPxyLineErrorGraph(&plot);
+
+        // copy data into datastore and immediately set the yColumn
+        graph->set_xColumn(columnX);
+        graph->set_yColumn(ds->addCopiedColumn(Y, "y"+QString::number(errorID)));
+        graph->set_xErrorColumn(columnXError);
+        graph->set_yErrorColumn(columnYError);
+
+        // set error style, for the y-axis
+        graph->set_yErrorStyle(errorStyles[errorID]);
+        // no error indicators for the x-values
+        graph->set_xErrorStyle(JKQTPnoError);
+        // ... unless: for some error styles we want error in both directions
+        if (showXandYError[errorID]) {
+            graph->set_xErrorStyle(errorStyles[errorID]);
+            graph->set_drawLine(false);
+        }
+        // make error indicator 30% transparent
+        QColor c=graph->get_errorFillColor();
+        c.setAlphaF(0.3);
+        graph->set_errorFillColor(c);
+        // set error indicator line width
+        graph->set_errorWidth(1);
+        // set length of small bars at the end of error bars
+        graph->set_errorbarSize(15);
+
+
+        // set symbol (cross/X) + pen style (and color)dashed)
+        graph->set_symbol(JKQTPcross);
+        graph->set_style(Qt::DashLine);
+        // set symbol size
+        graph->set_symbolSize(5);
+        // set width of symbol lines
+        graph->set_symbolWidth(1);
+        // set width of graph line
+        graph->set_lineWidth(1);
+
+        // graph title is made from symbol+errorStylestyle, we use the LaTeX instruction \verb around the
+        // result of JKQTPerrorPlotstyle2String(), because it contains underscores that would otherwise
+        // lead to lower-case letter, which we don't want
+        graph->set_title("\\verb{"+JKQTPerrorPlotstyle2String(errorStyles[errorID])+"}");
+
+        // add the graph to the plot, so it is actually displayed
+        plot.addGraph(graph);
+    }
+```
+
+The error styles are set in these lines:
+```c++
+	// set error style, for the y-axis
+	graph->set_yErrorStyle(errorStyles[errorID]);
+	// no error indicators for the x-values
+	graph->set_xErrorStyle(errorStyles[errorID]);
+```
+
+There are several variables that can be used to further style the error indicator, like:
+```c++
+	// make error indicator 30% transparent
+	QColor c=graph->get_errorFillColor();
+	c.setAlphaF(0.3);
+	graph->set_errorFillColor(c);
+	// set error indicator line width
+	graph->set_errorWidth(1);
+	// set length of small bars at the end of error bars
+	graph->set_errorbarSize(15);
+```
+
+There are more properties that you can find in the documentation of the mix-in classes `JKQTPxyGraphErrors`, `JKQTPxGraphErrors`, `JKQTPyGraphErrors`, `JKQTPgraphErrors`.
+
+In addition the plot key is moved outside the pot and the grid in the plot is switched off:
+```c++
+    // 6. change locaion of key (outside top-right)
+    plot.get_plotter()->set_keyPosition(JKQTPkeyOutsideRightTop);
+    // ... and switch off the grid
+    plot.getXAxis()->set_drawGrid(false);
+    plot.getXAxis()->set_drawMinorGrid(false);
+    plot.getYAxis()->set_drawGrid(false);
+    plot.getYAxis()->set_drawMinorGrid(false);
+```
+
+The result looks like this:
+
+![jkqtplotter_simpletest_errorbarstyles](https://raw.githubusercontent.com/jkriege2/JKQtPlotter/master/screenshots/jkqtplotter_simpletest_errorbarstyles.png)
+
+Error bars are implemented in the mixin-classes `JKQTPxyGraphErrors`, `JKQTPxGraphErrors` and `JKQTPyGraphErrors` that are all derived from `JKQTPgraphErrors`. With these it is simple to add error indicators to several different plot styles. Usually you can recognize these by looking at the class name, e.g. `JKQTPxyLineGraph` is a simple line+symbol graph, and `JKQTPxyLineErrorGraph` is the same with error indictaors (see above). There are also several other plots with error indicators:
+  - `JKQTPbarVerticalErrorGraph` for barcharts with errors:<br>![](https://raw.githubusercontent.com/jkriege2/JKQtPlotter/master/screenshots/jkqtplotter_simpletest_errorbarstyles_barcharts.png)
+  - `JKQTPimpulsesVerticalGraph` for impulse/candle-stick charts with errors:<br>![](https://raw.githubusercontent.com/jkriege2/JKQtPlotter/master/screenshots/jkqtplotter_simpletest_errorbarstyles_impulses.png)
+  - `JKQTPfilledCurveXErrorGraph` for filled curves with errors:<br>![](https://raw.githubusercontent.com/jkriege2/JKQtPlotter/master/screenshots/jkqtplotter_simpletest_errorbarstyles_filledcurves.png)
+.
+
+
+[Back to JKQTPlotter main page](https://github.com/jkriege2/JKQtPlotter/)

test/jkqtplotter_simpletest_errorbarstyles/jkqtplotter_simpletest_errorbarstyles.cpp

@@ -0,0 +1,109 @@
+#include <QApplication>
+#include "jkqtplotter/jkqtplotter.h"
+#include "jkqtplottertools/jkqtptools.h"
+
+
+int main(int argc, char* argv[])
+{
+    QApplication app(argc, argv);
+
+    // 1. create a plotter window and get a pointer to the internal datastore (for convenience)
+    JKQtPlotter plot;
+    JKQTPdatastore* ds=plot.getDatastore();
+
+    // 2. now we create data a vector of x-values for a simple plot
+    //    and generate some values for varying errors
+    //    y-data for the pot will be generated later to position the
+    //    plot at different locations.
+    QVector<double> X, Yerror, Xerror;
+    const int Ndata=7; // number of plot points in each curve
+    for (int i=0; i<Ndata; i++) {
+        const double x=10.0+double(i)*2.0;
+        X<<x;
+        Yerror<<0.35+0.3*sin(x);
+        Xerror<<0.35+0.3*sin(x);
+    }
+    // and copy it to the datastore
+    size_t columnX=ds->addCopiedColumn(X, "x");
+    size_t columnXError=ds->addCopiedColumn(Xerror, "xerror");
+    size_t columnYError=ds->addCopiedColumn(Yerror, "yerror");
+
+
+    // 3. now we make several plots with different error styles
+    //    for that we iterate over every style from the vector errorStyles
+    //    the array showXandYError indicates whether we want x- and y-error
+    //    for a style for all stywhere this is false, only y-error-indicators
+    //    are shown
+    QVector<JKQTPerrorPlotstyle> errorStyles    {JKQTPnoError, JKQTPerrorBars, JKQTPerrorSimpleBars, JKQTPerrorLines, JKQTPerrorPolygons, JKQTPerrorBoxes, JKQTPerrorEllipses, JKQTPerrorBarsPolygons, JKQTPerrorBarsLines, JKQTPerrorSimpleBarsLines, JKQTPerrorSimpleBarsPolygons };
+    QVector<bool>                showXandYError { false      , true          , true                , false          , false             , true           , true              , false                 , false              , false                    , false                        };
+
+    for (int errorID=0; errorID<errorStyles.size(); errorID++) {
+        // generate some plot data
+        QVector<double> Y;
+        for (auto& xx: X) {
+            Y<<xx*0.5+static_cast<double>(errorID)*2.5;
+        }
+
+        JKQTPxyLineErrorGraph* graph=new JKQTPxyLineErrorGraph(&plot);
+
+        // copy data into datastore and immediately set the yColumn
+        graph->set_xColumn(columnX);
+        graph->set_yColumn(ds->addCopiedColumn(Y, "y"+QString::number(errorID)));
+        graph->set_xErrorColumn(columnXError);
+        graph->set_yErrorColumn(columnYError);
+
+        // set error style, for the y-axis
+        graph->set_yErrorStyle(errorStyles[errorID]);
+        // no error indicators for the x-values
+        graph->set_xErrorStyle(JKQTPnoError);
+        // ... unless: for some error styles we want error in both directions
+        if (showXandYError[errorID]) {
+            graph->set_xErrorStyle(errorStyles[errorID]);
+            graph->set_drawLine(false);
+        }
+        // make error indicator 30% transparent
+        QColor c=graph->get_errorFillColor();
+        c.setAlphaF(0.3);
+        graph->set_errorFillColor(c);
+        // set error indicator line width
+        graph->set_errorWidth(1);
+        // set length of small bars at the end of error bars
+        graph->set_errorbarSize(15);
+
+
+        // set symbol (cross/X) + pen style (and color)dashed)
+        graph->set_symbol(JKQTPcross);
+        graph->set_style(Qt::DashLine);
+        // set symbol size
+        graph->set_symbolSize(5);
+        // set width of symbol lines
+        graph->set_symbolWidth(1);
+        // set width of graph line
+        graph->set_lineWidth(1);
+
+        // graph title is made from symbol+errorStylestyle, we use the LaTeX instruction \verb around the
+        // result of JKQTPerrorPlotstyle2String(), because it contains underscores that would otherwise
+        // lead to lower-case letter, which we don't want
+        graph->set_title("\\verb{"+JKQTPerrorPlotstyle2String(errorStyles[errorID])+"}");
+
+        // add the graph to the plot, so it is actually displayed
+        plot.addGraph(graph);
+    }
+
+    // 4. autoscale the plot so the graph is contained
+    plot.zoomToFit();
+
+    // 6. change locaion of key (outside top-right)
+    plot.get_plotter()->set_keyPosition(JKQTPkeyOutsideRightTop);
+    // ... and switch off the grid
+    plot.getXAxis()->set_drawGrid(false);
+    plot.getXAxis()->set_drawMinorGrid(false);
+    plot.getYAxis()->set_drawGrid(false);
+    plot.getYAxis()->set_drawMinorGrid(false);
+
+    // 7. show plotter and make it a decent size
+    plot.show();
+    plot.resize(800,600);
+
+    return app.exec();
+}

test/jkqtplotter_simpletest_errorbarstyles/jkqtplotter_simpletest_errorbarstyles.pro

@@ -0,0 +1,16 @@
+# source code for this simple demo
+SOURCES = jkqtplotter_simpletest_errorbarstyles.cpp 
+
+# configure Qt
+CONFIG += qt
+QT += core gui svg
+greaterThan(QT_MAJOR_VERSION, 4): QT += widgets printsupport
+
+# output executable name
+TARGET = jkqtplotter_simpletest_errorbarstyles
+
+# include JKQtPlotter source code
+include(../../lib/jkqtplotter.pri)
+# here you can activate some debug options
+#DEFINES += SHOW_JKQTPLOTTER_DEBUG
+#DEFINES += JKQTBP_AUTOTIMER