/** \example parametriccurve.cpp * Shows how to plot parametric curves from datapoints with JKQTPlotter * * \ref JKQTPlotterParametricCurves */ #include #include "jkqtplotter/jkqtplotter.h" #include "jkqtplotter/graphs/jkqtpscatter.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 X, Y, R; const int Ndata=500; // number of plot points in each curve const double phiMax=4.0*JKQTPSTATISTICS_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<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->setXColumn(columnX); graph1->setYColumn(columnY); graph1->setDrawLine(true); graph1->setSymbolType(JKQTPNoSymbol); graph1->setTitle("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->setXColumn(columnX); graph2->setYColumn(columnY); graph2->setColorColumn(columnR); graph2->setPalette(JKQTPMathImageMATLAB); graph2->setSymbolType(JKQTPNoSymbol); graph2->setDrawLine(true); graph2->setTitle("colored spiral"); graph2->getColorBarRightAxis()->setAxisLabel("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.getPlotter()->setMaintainAspectRatio(true); plot.getPlotter()->setAspectRatio(1); plot.getXAxis()->setAxisLabel("x-axis"); plot.getYAxis()->setAxisLabel("y-axis"); plot.getXAxis()->setDrawGrid(false); plot.getYAxis()->setDrawGrid(false); plot.setXY(-15,15,-15,15); plot2.getPlotter()->setMaintainAspectRatio(true); plot2.getPlotter()->setAspectRatio(1); plot2.getXAxis()->setAxisLabel("x-axis"); plot2.getYAxis()->setAxisLabel("y-axis"); plot2.getXAxis()->setDrawGrid(false); plot2.getYAxis()->setDrawGrid(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(); }