JKQTPlotter: added examples for custom symbols

doc/CMakeLists.txt

@@ -122,6 +122,7 @@ if(JKQtPlotter_BUILD_EXAMPLES)
     # the basenames are applied to the windows in the order of their windowTitle()s!
     set(JKQTPlotter_GenerateDocScreenshots_From
         scatter/scatter,scatter_error
+        scatter_customsymbol
         simpletest
         barchart/barchart,barchart_hor
         wiggleplots/wiggleplot_x,wiggleplot_y
@@ -151,6 +152,7 @@ if(JKQtPlotter_BUILD_EXAMPLES)
         impulsesplot
         parametriccurve/parametriccurve1,parametriccurve2
         paramscatterplot
+        paramscatterplot_customsymbol
         #paramscatterplot_image
         parsedfunctionplot
         rgbimageplot

doc/dox/examples_and_tutorials.dox

@@ -19,6 +19,9 @@ All test-projects are Qt-projects that use qmake to build. You can load them int
 <tr><td> \image html scatter_small.png 
     <td> \subpage JKQTPlotterscatter 
 	  <td> `JKQTPXYScatterGraph` <br> Iterator-Interface for JKQTDatastore
+<tr><td> \image html scatter_customsymbol_small.png 
+    <td> \subpage JKQTPlotterscatterCustomSymbol 
+	  <td> `JKQTPXYScatterGraph` <br>custom symbols JKQTPCharacterSymbol, JKQTPFilledCharacterSymbol, JKQTPRegisterCustomGraphSymbol()<br> Iterator-Interface for JKQTDatastore
 <tr><td> \image html speed_small.png
     <td> \subpage JKQTPlotterSpeedTest
     <td> `JKQTPXYLineGraph` <br> external `std::array<double,N>` data, not owned by datastore <br> live-data, measure plotting speed <br> tipps to increas plotting speed 
@@ -49,9 +52,12 @@ All test-projects are Qt-projects that use qmake to build. You can load them int
 <tr><td> \image html impulsesplot_small.png
     <td> \subpage JKQTPlotterImpulsePlots
     <td> `JKQTPImpulsesVerticalGraph` and `JKQTPImpulsesHorizontalGraph` <br> C++-style QVector as plot data 
-<tr><td> \image html paramscatterplot_small.png
-    <td> \subpage JKQTPlotterParamScatter
+<tr><td> \image html paramscatterplot_small.png
+    <td> \subpage JKQTPlotterParamScatter
     <td> `JKQTPXYParametrizedScatterGraph` <br> C++-style QVector as plot data <br> modify scatter/points/line-graph properties by data 
+<tr><td> \image html paramscatterplot_customsymbol_small.png
+    <td> \subpage JKQTPlotterparamscatterCustomSymbol
+    <td> `JKQTPXYParametrizedScatterGraph` <br>custom and varying symbols using JKQTPRegisterCustomGraphSymbol()<br>iterator interface to `JKQTPDatastore` 
 <tr><td> \image html paramscatterplot_image_small.png
     <td> \subpage JKQTPlotterParamScatterImage
     <td> `JKQTPXYParametrizedScatterGraph` <br> C++-style QVector as plot data <br> rectangular arrangement of scatters <br> generative computer graphics 

examples/CMakeLists.txt

@@ -77,12 +77,14 @@ add_subdirectory(multiplot)
 add_subdirectory(parametriccurve)
 add_subdirectory(paramscatterplot)
 add_subdirectory(paramscatterplot_image)
+add_subdirectory(paramscatterplot_customsymbol)
 add_subdirectory(parsedfunctionplot)
 add_subdirectory(rgbimageplot)
 add_subdirectory(rgbimageplot_cimg)
 add_subdirectory(rgbimageplot_opencv)
 add_subdirectory(rgbimageplot_qt)
 add_subdirectory(scatter)
+add_subdirectory(scatter_customsymbol)
 add_subdirectory(speed)
 add_subdirectory(stackedbars)
 add_subdirectory(stepplots)

examples/paramscatterplot_customsymbol/CMakeLists.txt

@@ -0,0 +1,33 @@
+cmake_minimum_required(VERSION 3.16)
+
+set(EXAMPLE_NAME paramscatterplot_customsymbol)
+set(EXENAME jkqtptest_${EXAMPLE_NAME})
+
+message( STATUS "..   Building Example ${EXAMPLE_NAME}" )
+
+
+# Set up source files
+set(SOURCES paramscatterplot_customsymbol.cpp )
+set(HEADERS  )
+set(RESOURCES  )
+set(UIS  )
+
+add_executable(${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(${EXENAME} JKQTPlotterSharedLib)
+endif()
+
+# precomiled headers to speed up compilation
+target_precompile_headers(${EXENAME} PRIVATE ../../lib/jkqtplotter/private/jkqtplotter_precomp.h)
+
+
+# Installation
+install(TARGETS ${EXENAME} RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})
+
+#Installation of Qt DLLs on Windows
+jkqtplotter_deployqt(${EXENAME})

examples/paramscatterplot_customsymbol/README.md

@@ -0,0 +1,69 @@
+# Example (JKQTPlotter): Parametrized Scatter-graph with custom symbols             {#JKQTPlotterparamscatterCustomSymbol}
+
+This project (see `./examples/paramscatterplot_customsymbol/`) demonstrates using JKQTPlotter to draw a parametrized scatter graph (JKQTPXYParametrizedScatterGraph) with custom symbols. To demonstrate this, we create a plot with several symbols, connected by a line, where each symbol shows a pie-chart with varying fractions.
+
+The source code of the example can be found in [`paramscatterplot_customsymbol.cpp`](https://github.com/jkriege2/JKQtPlotter/tree/master/examples/paramscatterplot_customsymbol/paramscatterplot_customsymbol.cpp).
+
+First we create a plotter window and get a pointer to the internal datastore (for convenience). Then we add three new datacolumns and obtain back inserters.
+```.cpp
+    JKQTPlotter plot;
+    JKQTPDatastore* ds=plot.getDatastore();
+
+    size_t columnX=ds->addColumn("x");
+    auto colXInserter=ds->backInserter(columnX);
+    size_t columnY=ds->addColumn("y");
+    auto colYInserter=ds->backInserter(columnY);
+    size_t columnS=ds->addColumn("sym");
+    auto colSInserter=ds->backInserter(columnS);
+```
+Now we define a functor that draws a pie chart with three segments with fractions `f1` (blue), `f2` (green) and `1.0-f1-f2` (yellow):
+```.cpp
+    auto pieFunc=[](QPainter& p, double f1, double f2) {
+            double f3=1.0-f1-f2;
+            QRectF rec(-0.5,-0.5,1,1);
+            p.setPen(QPen(QColor("black"), p.pen().width(), Qt::SolidLine));
+            p.setBrush(QBrush(QColor("blue")));
+            p.drawPie(rec, 90, -f1*360*16);
+            p.setBrush(QBrush(QColor("green")));
+            p.drawPie(rec, 90-f1*360*16, -f2*360*16);
+            p.setBrush(QBrush(QColor("yellow")));
+            p.drawPie(rec, 90-(f1+f2)*360*16, -f3*360*16);
+        };
+```
+Now we create data for the plot, x and y follow a simple function and the symbols are encoded in a separated column, where for each datapoint, we register a new symbol using JKQTPRegisterCustomGraphSymbol(), which is drawn by a differently parametrized (f1,f2) functor pieFunc.
+```.cpp
+    const int Ndata=5;
+    for (int i=0; i<Ndata; i++) {
+        // put data
+        const double x=double(i)/double(Ndata-1);
+        *(colXInserter++)=x;
+        *(colYInserter++)=pow(x*1.3, 2.0);
+        *(colSInserter++)=JKQTPRegisterCustomGraphSymbol(std::bind(pieFunc, std::placeholders::_1, x*0.4, 0.5-x*0.2));
+    }
+```
+Finally we create a graph in the plot, which displays our datasets:
+```.cpp
+    JKQTPXYParametrizedScatterGraph* graph1=new JKQTPXYParametrizedScatterGraph(&plot);
+    graph1->setXColumn(columnX);
+    graph1->setYColumn(columnY);
+    graph1->setSymbolSize(25);
+    graph1->setDrawLine(true);
+    graph1->setLineWidth(4);
+    graph1->setDrawLineInForeground(false);
+    graph1->setColor(QColor("black"));
+    graph1->setTitle(QObject::tr("pie scatter"));
+```    
+The symbol type is stored in columnS, note however how we have to give a  custom JKQTPXYParametrizedScatterGraph::symbolColumnFunctor, because the default one maps the values in the column to the range `[0...JKQTPMaxSymbolID]`  in a cycling fashion (using a mod operation), but here we want to use the `stored ID directly.
+```.cpp
+    graph1->setSymbolColumn(columnS);
+    graph1->setSymbolColumnFunctor(std::bind([](double /*x*/, double /*y*/, double symbolcolumn)->JKQTPGraphSymbols {
+        return static_cast<JKQTPGraphSymbols>(floor(symbolcolumn));
+    }, std::placeholders::_1, std::placeholders::_2, std::placeholders::_3));
+    plot.addGraph(graph1);
+```
+The result looks like this:
+
+![paramscatterplot_customsymbol](https://raw.githubusercontent.com/jkriege2/JKQtPlotter/master/screenshots/paramscatterplot_customsymbol.png)
+
+
+

examples/paramscatterplot_customsymbol/paramscatterplot_customsymbol.cpp

@@ -0,0 +1,96 @@
+/** \example scatter_customsymbol.cpp
+ * Usage of JKQTPScatterGraph with custom symbols
+ *
+ * \ref JKQTPlotterscatterCustomSymbol
+ */
+ 
+#include "jkqtpexampleapplication.h"
+#include <QApplication>
+#include "jkqtplotter/jkqtplotter.h"
+#include "jkqtplotter/graphs/jkqtpscatter.h"
+#include "jkqtpexampleapplication.h"
+#include <random>
+
+int main(int argc, char* argv[])
+{
+
+    JKQTPAppSettingController highDPIController(argc,argv);
+    JKQTPExampleApplication 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. add three columns to the JKQTPDatastore and obtain back-inserter iterators for these
+    size_t columnX=ds->addColumn("x");
+    auto colXInserter=ds->backInserter(columnX);
+    size_t columnY=ds->addColumn("y");
+    auto colYInserter=ds->backInserter(columnY);
+    size_t columnS=ds->addColumn("sym");
+    auto colSInserter=ds->backInserter(columnS);
+
+    // 3. now we define a functor that draws a pie chart with three segments with fractions
+    //    f1 (blue), f2 (green) and 1-f1-f2 (yellow)
+    auto pieFunc=[](QPainter& p, double f1, double f2) {
+            double f3=1.0-f1-f2;
+            QRectF rec(-0.5,-0.5,1,1);
+            p.setPen(QPen(QColor("black"), p.pen().width(), Qt::SolidLine));
+            p.setBrush(QBrush(QColor("blue")));
+            p.drawPie(rec, 90, -f1*360*16);
+            p.setBrush(QBrush(QColor("green")));
+            p.drawPie(rec, 90-f1*360*16, -f2*360*16);
+            p.setBrush(QBrush(QColor("yellow")));
+            p.drawPie(rec, 90-(f1+f2)*360*16, -f3*360*16);
+        };
+    // 4. now we create data for the plot, x and y follow a simple function
+    //    and the symbols are encoded in a separated column, where for each datapoint, we
+    //    register a new symbol using JKQTPRegisterCustomGraphSymbol(), which is drawn by
+    //    a differently parametrized (f1,f2) functor pieFunc.
+    const int Ndata=5;
+    for (int i=0; i<Ndata; i++) {
+        // put data
+        const double x=double(i)/double(Ndata-1);
+        *(colXInserter++)=x;
+        *(colYInserter++)=pow(x*1.3, 2.0);
+        *(colSInserter++)=JKQTPRegisterCustomGraphSymbol(std::bind(pieFunc, std::placeholders::_1, x*0.4, 0.5-x*0.2));
+    }
+
+
+    // 5. Finally we create a graph in the plot, which displays our datasets:
+    JKQTPXYParametrizedScatterGraph* graph1=new JKQTPXYParametrizedScatterGraph(&plot);
+    graph1->setXColumn(columnX);
+    graph1->setYColumn(columnY);
+    graph1->setSymbolSize(25);
+    graph1->setDrawLine(true);
+    graph1->setLineWidth(4);
+    graph1->setDrawLineInForeground(false);
+    graph1->setColor(QColor("black"));
+    graph1->setTitle(QObject::tr("pie scatter"));
+    // the symbol type is stored in columnS, note however how we have to give a
+    // custom JKQTPXYParametrizedScatterGraph::symbolColumnFunctor, because the
+    // default one maps the values in the column to the range [0...JKQTPMaxSymbolID]
+    // in a cycling fashion (using a mod operation), but here we want to use the
+    // stored ID directly.
+    graph1->setSymbolColumn(columnS);
+    graph1->setSymbolColumnFunctor(std::bind([](double /*x*/, double /*y*/, double symbolcolumn)->JKQTPGraphSymbols {
+        return static_cast<JKQTPGraphSymbols>(floor(symbolcolumn));
+    }, std::placeholders::_1, std::placeholders::_2, std::placeholders::_3));
+    plot.addGraph(graph1);
+
+
+    // 6. autoscale the plot so the graph is contained
+    plot.setXY(-0.2,1.2,-0.4,2.2);
+
+    // show plotter and make it a decent size
+    plot.getXAxis()->setShowZeroAxis(false);
+    plot.getYAxis()->setShowZeroAxis(false);
+    plot.setGrid(false);
+    plot.getPlotter()->setKeyPosition(JKQTPKeyInsideTopLeft);
+    plot.getPlotter()->setPlotLabel(QObject::tr("Custom Parametrized Scatter Symbols Example"));
+    plot.show();
+    plot.resize(500/plot.devicePixelRatioF(),400/plot.devicePixelRatioF());
+
+
+    return app.exec();
+}

examples/scatter_customsymbol/CMakeLists.txt

@@ -0,0 +1,33 @@
+cmake_minimum_required(VERSION 3.16)
+
+set(EXAMPLE_NAME scatter_customsymbol)
+set(EXENAME jkqtptest_${EXAMPLE_NAME})
+
+message( STATUS "..   Building Example ${EXAMPLE_NAME}" )
+
+
+# Set up source files
+set(SOURCES scatter_customsymbol.cpp )
+set(HEADERS  )
+set(RESOURCES  )
+set(UIS  )
+
+add_executable(${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(${EXENAME} JKQTPlotterSharedLib)
+endif()
+
+# precomiled headers to speed up compilation
+target_precompile_headers(${EXENAME} PRIVATE ../../lib/jkqtplotter/private/jkqtplotter_precomp.h)
+
+
+# Installation
+install(TARGETS ${EXENAME} RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})
+
+#Installation of Qt DLLs on Windows
+jkqtplotter_deployqt(${EXENAME})

examples/scatter_customsymbol/README.md

@@ -0,0 +1,113 @@
+# Example (JKQTPlotter): Scatter-graph with custom symbols             {#JKQTPlotterscatterCustomSymbol}
+
+This project (see `./examples/scatter_customsymbol/`) demonstrates using JKQTPlotter to draw a scatter graph (JKQTPXYScatterGraph) with custom symbols. 
+
+The source code of the example can be found in [`jkqtplotter_scatter.cpp`](https://github.com/jkriege2/JKQtPlotter/tree/master/examples/scatter_customsymbol/scatter_customsymbol.cpp).
+
+First we create a plotter window and get a pointer to the internal datastore (for convenience):
+```.cpp
+    JKQTPlotter plot;
+    JKQTPDatastore* ds=plot.getDatastore();
+```
+Now we add several columns to the JKQTPDatastore and obtain back-inserter iterators for these:
+```.cpp
+    size_t columnX=ds->addColumn("x");
+    auto colXInserter=ds->backInserter(columnX);
+    size_t columnY1=ds->addColumn("y1");
+    auto colY1Inserter=ds->backInserter(columnY1);
+    size_t columnY2=ds->addColumn("y2");
+    auto colY2Inserter=ds->backInserter(columnY2);
+    size_t columnY3=ds->addColumn("y3");
+    auto colY3Inserter=ds->backInserter(columnY3);
+    size_t columnY4=ds->addColumn("y4");
+    auto colY4Inserter=ds->backInserter(columnY4);
+```
+... and fill the columns with data
+```.cpp
+    const int Ndata=5;
+    for (int i=0; i<Ndata; i++) {
+        // put data
+        const double x=double(i)/double(Ndata-1);
+        *(colXInserter++)=x;
+        *(colY1Inserter++)=3.0+pow(x*1.3, 2.0)*1.3;
+        *(colY2Inserter++)=2.0+pow(x*1.3, 2.0)*1.2;
+        *(colY3Inserter++)=1.0+pow(x*1.3, 2.0)*1.1;
+        *(colY4Inserter++)=pow(x*1.3, 2.0);
+    }
+```
+Now we create several graph objects of type JKQTPXYScatterGraph. Each one uses a different custom symbol style:
+
+Graphs `graph3` and `graph4` use `JKQTPCharacterSymbol` and `JKQTPFilledCharacterSymbol` respectively to draw spades and hearts from the unicode characters `U+2660` and `U+2665` respectively. The two graphs differ in the coloring of the symbols. The `JKQTPCharacterSymbol` variant would use the color default (cycling) graph color, but here we overwrite this with `darkblue`. The `JKQTPFilledCharacterSymbol` variant uses red filled hearts with a thin black border.
+```.cpp
+    JKQTPXYScatterGraph* graph3=new JKQTPXYScatterGraph(&plot);
+    graph3->setXColumn(columnX);
+    graph3->setYColumn(columnY3);
+    graph3->setSymbolType(JKQTPCharacterSymbol+QChar(0x2660).unicode());
+    graph3->setSymbolColor(QColor("darkblue"));
+    graph3->setSymbolSize(15);
+    graph3->setTitle(QObject::tr("spades"));
+    plot.addGraph(graph3);
+
+    JKQTPXYScatterGraph* graph4=new JKQTPXYScatterGraph(&plot);
+    graph4->setXColumn(columnX);
+    graph4->setYColumn(columnY4);
+    graph4->setSymbolType(JKQTPFilledCharacterSymbol+QChar(0x2665).unicode());
+    graph4->setSymbolSize(20);
+    graph4->setSymbolColor(QColor("black"));
+    graph4->setSymbolFillColor(QColor("red"));
+    graph4->setSymbolLineWidth(0.5);
+    graph4->setTitle(QObject::tr("hearts"));
+    plot.addGraph(graph4);
+```
+
+The more advanced graphs `graph1` and `graph2` use `JKQTPRegisterCustomGraphSymbol()` to register functors that draw user-specific symbols:
+```.cpp
+    JKQTPCustomGraphSymbolFunctor f=[](QPainter& p) {
+        p.setBrush(Qt::NoBrush); // ensure that circles are not drawn filled
+        p.drawEllipse(QPointF(-0.33, -0.33/4.0), 0.33/2.0, 0.33/2.0);
+        p.drawEllipse(QPointF(0, -0.33/4.0), 0.33/2.0, 0.33/2.0);
+        p.drawEllipse(QPointF(0.33, -0.33/4.0), 0.33/2.0, 0.33/2.0);
+        p.drawEllipse(QPointF(-0.33/2.0, 0.33/4.0), 0.33/2.0, 0.33/2.0);
+        p.drawEllipse(QPointF(0.33/2.0, 0.33/4.0), 0.33/2.0, 0.33/2.0);
+    };
+    JKQTPGraphSymbols customsymbol_olympicrings=JKQTPRegisterCustomGraphSymbol(f);
+    JKQTPXYScatterGraph* graph1=new JKQTPXYScatterGraph(&plot);
+    graph1->setXColumn(columnX);
+    graph1->setYColumn(columnY1);
+    graph1->setSymbolType(customsymbol_olympicrings);
+    graph1->setSymbolSize(30);
+    graph1->setTitle(QObject::tr("olympics"));
+    plot.addGraph(graph1);
+
+
+    JKQTPGraphSymbols customsymbol_coloredolympicrings=JKQTPRegisterCustomGraphSymbol(
+                [](QPainter& p) {
+                        p.setBrush(Qt::NoBrush); // ensure that circles are not drawn filled
+                        const double w=p.pen().widthF();
+                        p.setPen(QPen(QColor("red"), w));
+                        p.drawEllipse(QPointF(-0.33, -0.33/4.0), 0.33/2.0, 0.33/2.0);
+                        p.setPen(QPen(QColor("black"), w));
+                        p.drawEllipse(QPointF(0, -0.33/4.0), 0.33/2.0, 0.33/2.0);
+                        p.setPen(QPen(QColor("gold"), w));
+                        p.drawEllipse(QPointF(0.33, -0.33/4.0), 0.33/2.0, 0.33/2.0);
+                        p.setPen(QPen(QColor("darkgreen"), w));
+                        p.drawEllipse(QPointF(-0.33/2.0, 0.33/4.0), 0.33/2.0, 0.33/2.0);
+                        p.setPen(QPen(QColor("darkblue"), w));
+                        p.drawEllipse(QPointF(0.33/2.0, 0.33/4.0), 0.33/2.0, 0.33/2.0);
+                    });
+    JKQTPXYScatterGraph* graph2=new JKQTPXYScatterGraph(&plot);
+    graph2->setXColumn(columnX);
+    graph2->setYColumn(columnY2);
+    graph2->setSymbolType(customsymbol_coloredolympicrings);
+    graph2->setSymbolSize(30);
+    graph2->setTitle(QObject::tr("colored olympics"));
+    plot.addGraph(graph2);                    
+```
+Bothe variant show the olympic rings. `graph1` uses the (cycling) default graph color and `graph2` draws with user-defined colors.
+
+The result looks like this:
+
+![scatter_customsymbol](https://raw.githubusercontent.com/jkriege2/JKQtPlotter/master/screenshots/scatter_customsymbol.png)
+
+
+

examples/scatter_customsymbol/scatter_customsymbol.cpp

@@ -0,0 +1,127 @@
+/** \example scatter_customsymbol.cpp
+ * Usage of JKQTPScatterGraph with custom symbols
+ *
+ * \ref JKQTPlotterscatterCustomSymbol
+ */
+ 
+#include "jkqtpexampleapplication.h"
+#include <QApplication>
+#include "jkqtplotter/jkqtplotter.h"
+#include "jkqtplotter/graphs/jkqtpscatter.h"
+#include "jkqtpexampleapplication.h"
+#include <random>
+
+int main(int argc, char* argv[])
+{
+
+    JKQTPAppSettingController highDPIController(argc,argv);
+    JKQTPExampleApplication 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. add two columns to the JKQTPDatastore and obtain back-inserter iterators for these
+    size_t columnX=ds->addColumn("x");
+    auto colXInserter=ds->backInserter(columnX);
+    size_t columnY1=ds->addColumn("y1");
+    auto colY1Inserter=ds->backInserter(columnY1);
+    size_t columnY2=ds->addColumn("y2");
+    auto colY2Inserter=ds->backInserter(columnY2);
+    size_t columnY3=ds->addColumn("y3");
+    auto colY3Inserter=ds->backInserter(columnY3);
+    size_t columnY4=ds->addColumn("y4");
+    auto colY4Inserter=ds->backInserter(columnY4);
+
+
+    // 3. now we create data for a simple plot (a sine curve with random noise)
+    const int Ndata=5;
+    for (int i=0; i<Ndata; i++) {
+        // put data
+        const double x=double(i)/double(Ndata-1);
+        *(colXInserter++)=x;
+        *(colY1Inserter++)=3.0+pow(x*1.3, 2.0)*1.3;
+        *(colY2Inserter++)=2.0+pow(x*1.3, 2.0)*1.2;
+        *(colY3Inserter++)=1.0+pow(x*1.3, 2.0)*1.1;
+        *(colY4Inserter++)=pow(x*1.3, 2.0);
+    }
+
+    // 4. define custom symbol
+    JKQTPCustomGraphSymbolFunctor f=[](QPainter& p) {
+        p.setBrush(Qt::NoBrush); // ensure that circles are not drawn filled
+        p.drawEllipse(QPointF(-0.33, -0.33/4.0), 0.33/2.0, 0.33/2.0);
+        p.drawEllipse(QPointF(0, -0.33/4.0), 0.33/2.0, 0.33/2.0);
+        p.drawEllipse(QPointF(0.33, -0.33/4.0), 0.33/2.0, 0.33/2.0);
+        p.drawEllipse(QPointF(-0.33/2.0, 0.33/4.0), 0.33/2.0, 0.33/2.0);
+        p.drawEllipse(QPointF(0.33/2.0, 0.33/4.0), 0.33/2.0, 0.33/2.0);
+    };
+    JKQTPGraphSymbols customsymbol_olympicrings=JKQTPRegisterCustomGraphSymbol(f);
+
+    JKQTPGraphSymbols customsymbol_coloredolympicrings=JKQTPRegisterCustomGraphSymbol(
+                [](QPainter& p) {
+                        p.setBrush(Qt::NoBrush); // ensure that circles are not drawn filled
+                        const double w=p.pen().widthF();
+                        p.setPen(QPen(QColor("red"), w));
+                        p.drawEllipse(QPointF(-0.33, -0.33/4.0), 0.33/2.0, 0.33/2.0);
+                        p.setPen(QPen(QColor("black"), w));
+                        p.drawEllipse(QPointF(0, -0.33/4.0), 0.33/2.0, 0.33/2.0);
+                        p.setPen(QPen(QColor("gold"), w));
+                        p.drawEllipse(QPointF(0.33, -0.33/4.0), 0.33/2.0, 0.33/2.0);
+                        p.setPen(QPen(QColor("darkgreen"), w));
+                        p.drawEllipse(QPointF(-0.33/2.0, 0.33/4.0), 0.33/2.0, 0.33/2.0);
+                        p.setPen(QPen(QColor("darkblue"), w));
+                        p.drawEllipse(QPointF(0.33/2.0, 0.33/4.0), 0.33/2.0, 0.33/2.0);
+                    });
+
+    // 4. create graphs in the plot, which plots the datasets:
+    JKQTPXYScatterGraph* graph1=new JKQTPXYScatterGraph(&plot);
+    graph1->setXColumn(columnX);
+    graph1->setYColumn(columnY1);
+    graph1->setSymbolType(customsymbol_olympicrings);
+    graph1->setSymbolSize(30);
+    graph1->setTitle(QObject::tr("olympics"));
+    plot.addGraph(graph1);
+
+    JKQTPXYScatterGraph* graph2=new JKQTPXYScatterGraph(&plot);
+    graph2->setXColumn(columnX);
+    graph2->setYColumn(columnY2);
+    graph2->setSymbolType(customsymbol_coloredolympicrings);
+    graph2->setSymbolSize(30);
+    graph2->setTitle(QObject::tr("colored olympics"));
+    plot.addGraph(graph2);
+
+    JKQTPXYScatterGraph* graph3=new JKQTPXYScatterGraph(&plot);
+    graph3->setXColumn(columnX);
+    graph3->setYColumn(columnY3);
+    graph3->setSymbolType(JKQTPCharacterSymbol+QChar(0x2660).unicode());
+    graph3->setSymbolColor(QColor("darkblue"));
+    graph3->setSymbolSize(15);
+    graph3->setTitle(QObject::tr("spades"));
+    plot.addGraph(graph3);
+
+    JKQTPXYScatterGraph* graph4=new JKQTPXYScatterGraph(&plot);
+    graph4->setXColumn(columnX);
+    graph4->setYColumn(columnY4);
+    graph4->setSymbolType(JKQTPFilledCharacterSymbol+QChar(0x2665).unicode());
+    graph4->setSymbolSize(20);
+    graph4->setSymbolColor(QColor("black"));
+    graph4->setSymbolFillColor(QColor("red"));
+    graph4->setSymbolLineWidth(0.5);
+    graph4->setTitle(QObject::tr("hearts"));
+    plot.addGraph(graph4);
+
+    // 6. autoscale the plot so the graph is contained
+    plot.setXY(-0.1,1.1,-1, 6);
+
+    // show plotter and make it a decent size
+    plot.getXAxis()->setShowZeroAxis(false);
+    plot.getYAxis()->setShowZeroAxis(false);
+    plot.setGrid(false);
+    plot.getPlotter()->setKeyPosition(JKQTPKeyInsideTopLeft);
+    plot.getPlotter()->setPlotLabel(QObject::tr("Custom Scatter Symbols Example"));
+    plot.show();
+    plot.resize(500/plot.devicePixelRatioF(),500/plot.devicePixelRatioF());
+
+    return app.exec();
+}