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#include <stdlib.h>
#include <qapplication.h>
#include <qpen.h>
#include <qwt_plot.h>
#include <qwt_plot_grid.h>
#include <qwt_plot_marker.h>
#include <qwt_interval_data.h>
#include "histogram_item.h"
int main(int argc, char **argv)
{
QApplication a(argc, argv);
QwtPlot plot;
plot.setCanvasBackground(QColor(Qt::white));
plot.setTitle("Histogram");
QwtPlotGrid *grid = new QwtPlotGrid;
grid->enableXMin(true);
grid->enableYMin(true);
grid->setMajPen(QPen(Qt::black, 0, Qt::DotLine));
grid->setMinPen(QPen(Qt::gray, 0 , Qt::DotLine));
grid->attach(&plot);
HistogramItem *histogram = new HistogramItem();
histogram->setColor(Qt::darkCyan);
const int numValues = 20;
QwtArray<QwtDoubleInterval> intervals(numValues);
QwtArray<double> values(numValues);
double pos = 0.0;
for ( int i = 0; i < (int)intervals.size(); i++ )
{
const int width = 5 + rand() % 15;
const int value = rand() % 100;
intervals[i] = QwtDoubleInterval(pos, pos + double(width));
values[i] = value;
pos += width;
}
histogram->setData(QwtIntervalData(intervals, values));
histogram->attach(&plot);
plot.setAxisScale(QwtPlot::yLeft, 0.0, 100.0);
plot.setAxisScale(QwtPlot::xBottom, 0.0, pos);
plot.replot();
#if QT_VERSION < 0x040000
a.setMainWidget(&plot);
#endif
plot.resize(600,400);
plot.show();
return a.exec();
}
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