added example that shows how to draw parametric curves

JKQtPlotterBuildAllExamples.pro

@@ -51,6 +51,7 @@ addSimpleTest(speed)
 addSimpleTest(rgbimageplot_qt)
 addSimpleTest(impulsesplot)
 addSimpleTest(paramscatterplot)
+addSimpleTest(parametriccurve)
 #addSimpleTest(imageplot_nodatastore)
 #addSimpleTest(rgbimageplot_opencv)
 #addSimpleTest(imageplot_opencv)

README.md

@@ -27,7 +27,8 @@ All test-projects are Qt-projects that use qmake to build. You can load them int
 | [![](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/simpletest_stackedbars) | [Stacked Bar Charts](https://github.com/jkriege2/JKQtPlotter/tree/master/test/simpletest_stackedbars) | `JKQTPbarVerticalStackableGraph`, `JKQTPbarHorizontalStackableGraph`<br/>C++-style vectors of data |
 | [![](https://raw.githubusercontent.com/jkriege2/JKQtPlotter/master/screenshots/jkqtplotter_simpletest_filledgraphs_small.png)](https://github.com/jkriege2/JKQtPlotter/tree/master/test/simpletest_filledgraphs) | [Filled Curve Plots](https://github.com/jkriege2/JKQtPlotter/tree/master/test/simpletest_filledgraphs) | `JKQTPbarVerticalGraph`<br/>setting/altering data in `JKQTPdatstore` directly<br/> transparent plots<br/>calculating histograms |
 | [![](https://raw.githubusercontent.com/jkriege2/JKQtPlotter/master/screenshots/jkqtplotter_simpletest_impulsesplot_small.png)](https://github.com/jkriege2/JKQtPlotter/tree/master/test/simpletest_impulsesplot) | [Impulse Plots](https://github.com/jkriege2/JKQtPlotter/tree/master/test/simpletest_impulsesplot) | `JKQTPimpulsesVerticalGraph` and `JKQTPimpulsesHorizontalGraph`<br/>C++-style QVector as plot data |
-| [![](https://raw.githubusercontent.com/jkriege2/JKQtPlotter/master/screenshots/jkqtplotter_simpletest_paramscatterplot_small.png)](https://github.com/jkriege2/JKQtPlotter/tree/master/test/simpletest_paramscatterplot) | [Scatter Graph with Parametrized Symbols/Colors](https://github.com/jkriege2/JKQtPlotter/tree/master/test/simpletest_paramscatterplot) | `JKQTPimpulsesVerticalGraph` and `JKQTPimpulsesHorizontalGraph`<br/>C++-style QVector as plot data |
+| [![](https://raw.githubusercontent.com/jkriege2/JKQtPlotter/master/screenshots/jkqtplotter_simpletest_paramscatterplot_small.png)](https://github.com/jkriege2/JKQtPlotter/tree/master/test/simpletest_paramscatterplot) | [Scatter Graph with Parametrized Symbols/Colors](https://github.com/jkriege2/JKQtPlotter/tree/master/test/simpletest_paramscatterplot) | `JKQTPxyParametrizedScatterGraph`<br/>C++-style QVector as plot data<br/>modify scatter/points/line-graph properties by data |
+| [![](https://raw.githubusercontent.com/jkriege2/JKQtPlotter/master/screenshots/jkqtplotter_simpletest_parametriccurve_small.png)](https://github.com/jkriege2/JKQtPlotter/tree/master/test/simpletest_parametriccurve) | [Plotting Parametric Curves](https://github.com/jkriege2/JKQtPlotter/tree/master/test/simpletest_parametriccurve) | `JKQTPxyLineGraph` and `JKQTPxyParametrizedScatterGraph`<br/>C++-style QVector as plot data<br/>parametric curve plotting |
 
 ### Styling the Plot, Keys, Axes, ...
 

test/simpletest_parametriccurve/README.md

@@ -0,0 +1,64 @@
+[Back to JKQTPlotter main page](https://github.com/jkriege2/JKQtPlotter/)
+
+# JKQtPlotter
+
+## Plotting Parametric Curves
+This project (see `./test/simpletest_parametriccurve/`) demonstrates how to draw parametric curves, using [`JKQTPxyLineGraph`}(https://github.com/jkriege2/JKQtPlotter/tree/master/test/simpletest) and [`JKQTPxyParametrizedScatterGraph`](https://github.com/jkriege2/JKQtPlotter/tree/master/test/simpletest_paramscatterplot). 
+
+The source code of the main application can be found in  [`jkqtplotter_simpletest_parametriccurve.cpp`](https://github.com/jkriege2/JKQtPlotter/blob/master/test/simpletest_parametriccurve/jkqtplotter_simpletest_parametriccurve.cpp). First, the parametric curve (here a [logarithic spiral](https://en.wikipedia.org/wiki/Logarithmic_spiral)) is sampled into two columns containing the x- and y-values along the curve. In addition the radial distance from x=y=0 is added into a third column:
+```c++
+    QVector<double> X, Y, R;
+    const int Ndata=500; // number of plot points in each curve
+    const double phiMax=4.0*M_PI;
+    const double a=1;
+    const double k=0.2;
+    for (double phi=-phiMax; phi<=phiMax; phi+=phiMax/double(Ndata)) {
+        const double x=a*exp(k*phi)*cos(phi);
+        const double y=a*exp(k*phi)*sin(phi);
+        X<<x;
+        Y<<y;
+        R<<sqrt(x*x+y*y);
+    }
+    // and copy it to the datastore
+    size_t columnX=ds->addCopiedColumn(X, "x");
+    size_t columnY=ds->addCopiedColumn(Y, "y");
+    size_t columnR=ds->addCopiedColumn(R, "r");
+```
+
+
+Then simples graph just uses the columns X and Y to plot the curve:
+```c++
+    JKQTPxyLineGraph* graph1=new JKQTPxyLineGraph(&plot);
+    graph1->set_xColumn(columnX);
+    graph1->set_yColumn(columnY);
+    graph1->set_drawLine(true);
+    graph1->set_symbol(JKQTPnoSymbol);
+    graph1->set_title("one-colored spiral");
+    plot.addGraph(graph1);
+```
+ 
+If you use `JKQTPxyParametrizedScatterGraph` instead of `JKQTPxyLineGraph`, you can also modify the color of the line-segments, connecting the datapoints:
+```c++
+    JKQTPxyParametrizedScatterGraph* graph2=new JKQTPxyParametrizedScatterGraph(&plot2);
+    graph2->set_xColumn(columnX);
+    graph2->set_yColumn(columnY);
+    graph2->set_colorColumn(columnR);
+    graph2->set_palette(JKQTPMathImageMATLAB);
+    graph2->set_symbol(JKQTPnoSymbol);
+    graph2->set_drawLine(true);
+    graph2->set_title("colored spiral");
+    graph2->get_colorBarRightAxis()->set_axisLabel("color scale radius $r(\\phi)$");
+    plot2.addGraph(graph2);
+```
+
+The result looks like this:
+
+![jkqtplotter_simpletest_parametriccurve](https://raw.githubusercontent.com/jkriege2/JKQtPlotter/master/screenshots/jkqtplotter_simpletest_parametriccurve1.png)
+
+... and with the line-color set by the radius:
+
+![jkqtplotter_simpletest_parametriccurve](https://raw.githubusercontent.com/jkriege2/JKQtPlotter/master/screenshots/jkqtplotter_simpletest_parametriccurve2.png)
+
+
+
+[Back to JKQTPlotter main page](https://github.com/jkriege2/JKQtPlotter/)

test/simpletest_parametriccurve/jkqtplotter_simpletest_parametriccurve.cpp

@@ -0,0 +1,87 @@
+#include <QApplication>
+#include "jkqtplotter/jkqtplotter.h"
+#include "jkqtplotter/jkqtpelements.h"
+
+
+int main(int argc, char* argv[])
+{
+    QApplication app(argc, argv);
+
+    // 1. create two plotter windows that share the same internal datastore (for convenience)
+    JKQtPlotter plot, plot2;
+    JKQTPdatastore* ds=plot.getDatastore();
+    plot2.useExternalDatastore(ds);
+
+    // 2. now we create a vector of x- and y-values of the logarithmic spiral
+    //    in addition the radius is stored in column R
+    QVector<double> X, Y, R;
+    const int Ndata=500; // number of plot points in each curve
+    const double phiMax=4.0*M_PI;
+    const double a=1;
+    const double k=0.2;
+    for (double phi=-phiMax; phi<=phiMax; phi+=phiMax/double(Ndata)) {
+        const double x=a*exp(k*phi)*cos(phi);
+        const double y=a*exp(k*phi)*sin(phi);
+        X<<x;
+        Y<<y;
+        R<<sqrt(x*x+y*y);
+    }
+    // and copy it to the datastore
+    size_t columnX=ds->addCopiedColumn(X, "x");
+    size_t columnY=ds->addCopiedColumn(Y, "y");
+    size_t columnR=ds->addCopiedColumn(R, "r");
+
+
+    // 3. now we make several graphs. In each one, another property of the graph is controlled by
+    //    a datacolumn
+
+    // 3.1 the basic graph
+    JKQTPxyLineGraph* graph1=new JKQTPxyLineGraph(&plot);
+    graph1->set_xColumn(columnX);
+    graph1->set_yColumn(columnY);
+    graph1->set_drawLine(true);
+    graph1->set_symbol(JKQTPnoSymbol);
+    graph1->set_title("one-colored spiral");
+    plot.addGraph(graph1);
+
+    // 3.2 for graph2 is the same as graph 1, but in addition, the color of the lines
+    //     is set, based on the contents of column R, via the color-palette JKQTPMathImageMATLAB
+    JKQTPxyParametrizedScatterGraph* graph2=new JKQTPxyParametrizedScatterGraph(&plot2);
+    graph2->set_xColumn(columnX);
+    graph2->set_yColumn(columnY);
+    graph2->set_colorColumn(columnR);
+    graph2->set_palette(JKQTPMathImageMATLAB);
+    graph2->set_symbol(JKQTPnoSymbol);
+    graph2->set_drawLine(true);
+    graph2->set_title("colored spiral");
+    graph2->get_colorBarRightAxis()->set_axisLabel("color scale radius $r(\\phi)$");
+    plot2.addGraph(graph2);
+
+
+    // 4. set the axis scale aspect ratios to 1,
+    //    autoscale the plot so the graph is contained
+    //    and format the coordinate system and key
+    plot.get_plotter()->set_maintainAspectRatio(true);
+    plot.get_plotter()->set_aspectRatio(1);
+    plot.getXAxis()->set_axisLabel("x-axis");
+    plot.getYAxis()->set_axisLabel("y-axis");
+    plot.getXAxis()->set_drawGrid(false);
+    plot.getYAxis()->set_drawGrid(false);
+    plot.setXY(-15,15,-15,15);
+    plot2.get_plotter()->set_maintainAspectRatio(true);
+    plot2.get_plotter()->set_aspectRatio(1);
+    plot2.getXAxis()->set_axisLabel("x-axis");
+    plot2.getYAxis()->set_axisLabel("y-axis");
+    plot2.getXAxis()->set_drawGrid(false);
+    plot2.getYAxis()->set_drawGrid(false);
+    plot2.setXY(-15,15,-15,15);
+
+
+    // 5. show plotters and make them a decent size
+    plot.show();
+    plot.resize(600,600);
+    plot2.show();
+    plot2.resize(600,600);
+
+    return app.exec();
+}

test/simpletest_parametriccurve/jkqtplotter_simpletest_parametriccurve.pro

@@ -0,0 +1,23 @@
+# source code for this simple demo
+SOURCES = jkqtplotter_simpletest_parametriccurve.cpp 
+
+# configure Qt
+CONFIG += qt
+QT += core gui xml  svg
+greaterThan(QT_MAJOR_VERSION, 4): QT += widgets printsupport
+
+# output executable name
+TARGET = jkqtplotter_simpletest_parametriccurve
+
+
+# include JKQtPlotter source code
+DEPENDPATH += . ../../lib
+INCLUDEPATH += ../../lib
+CONFIG (debug, debug|release):LIBS += -L../../lib/debug -ljkqtplotterlib
+CONFIG (release):LIBS += -L../../lib/release -ljkqtplotterlib
+
+win32-msvc*: DEFINES += _USE_MATH_DEFINES
+
+# here you can activate some debug options
+#DEFINES += SHOW_JKQTPLOTTER_DEBUG
+#DEFINES += JKQTBP_AUTOTIMER

test/simpletest_parametriccurve/jkqtplotter_simpletest_parametriccurve_and_lib.pro

@@ -0,0 +1,8 @@
+TEMPLATE = subdirs
+
+SUBDIRS +=  jkqtplotterlib jkqtplotter_simpletest_parametriccurve
+
+jkqtplotterlib.file = ../../lib/jkqtplotterlib.pro
+
+jkqtplotter_simpletest_parametriccurve.file=$$PWD/jkqtplotter_simpletest_parametriccurve.pro
+jkqtplotter_simpletest_parametriccurve.depends = jkqtplotterlib