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