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#include "mainwindow.h"
#include "plot.h"
#include <qmath.h>
static double randomValue()
{
// a number between [ 0.0, 1.0 ]
return ( qrand() % 100000 ) / 100000.0;
}
MainWindow::MainWindow()
{
d_plot = new Plot( this );
d_plot->setTitle( "Scatter Plot" );
setCentralWidget( d_plot );
// a million points
setSamples( 100000 );
}
void MainWindow::setSamples( int numPoints )
{
QPolygonF samples;
for ( int i = 0; i < numPoints; i++ )
{
const double x = randomValue() * 24.0 + 1.0;
const double y = ::log( 10.0 * ( x - 1.0 ) + 1.0 )
* ( randomValue() * 0.5 + 0.9 );
samples += QPointF( x, y );
}
d_plot->setSamples( samples );
}
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