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#ifdef QWT_QTOPIA
#include <qpe/qpeapplication.h>
#endif
#include <qapplication.h>
#include <qwt_plot.h>
#include <qwt_data.h>
#include <math.h>
//-----------------------------------------------------------------
// simple.cpp
//
// A simple example which shows how to use QwtPlot and QwtData
//-----------------------------------------------------------------
class SimpleData: public QwtData
{
// The x values depend on its index and the y values
// can be calculated from the corresponding x value.
// So we dont need to store the values.
// Such an implementation is slower because every point
// has to be recalculated for every replot, but it demonstrates how
// QwtData can be used.
public:
SimpleData(double(*y)(double), size_t size):
d_size(size),
d_y(y)
{
}
virtual QwtData *copy() const
{
return new SimpleData(d_y, d_size);
}
virtual size_t size() const
{
return d_size;
}
virtual double x(size_t i) const
{
return 0.1 * i;
}
virtual double y(size_t i) const
{
return d_y(x(i));
}
private:
size_t d_size;
double(*d_y)(double);
};
class Plot : public QwtPlot
{
public:
Plot();
};
Plot::Plot()
{
setTitle("A Simple QwtPlot Demonstration");
setAutoLegend(TRUE); // We want a legend
setLegendPosition(QwtPlot::Right);
// Set axis titles
setAxisTitle(xBottom, "x -->");
setAxisTitle(yLeft, "y -->");
// Insert new curves
long cSin = insertCurve("y = sin(x)");
long cCos = insertCurve("y = cos(x)");
// Set curve styles
setCurvePen(cSin, QPen(Qt::red));
setCurvePen(cCos, QPen(Qt::blue));
// Create sin and cos data
const int nPoints = 100;
setCurveData(cSin, SimpleData(::sin, nPoints));
setCurveData(cCos, SimpleData(::cos, nPoints));
// Insert markers
// ...a horizontal line at y = 0...
long mY = insertLineMarker("y = 0", QwtPlot::yLeft);
setMarkerYPos(mY, 0.0);
// ...a vertical line at x = 2 * pi
long mX = insertLineMarker("x = 2 pi", QwtPlot::xBottom);
setMarkerXPos(mX, 6.284);
replot();
}
int main(int argc, char **argv)
{
#ifdef QWT_QTOPIA
QPEApplication a(argc, argv);
#else
QApplication a(argc, argv);
#endif
Plot plot;
a.setMainWidget(&plot);
plot.resize(500,300);
plot.show();
return a.exec();
}
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