Hi,
Qwt Spectrogram looks great, but by default is uses double x, y, data as if the routine is supposed to perform some sort of maths on them. What I need to do is plot data from a few QList<double>'s. I have half stolen the code from the spectrogram example but I think my problem is in the value routine where it seems to crash. The data I am trying to plot is held in "QList<double> spectData[180];" Could you provide some pointers as to how to do it correctly?

Cheers.

Qt Code: 
  1. class SpectrogramData: public QwtRasterData
  2. {
  3. public:
  4. 	QpnwPhasedArrayPlot * parent;
  5. 	// Provide pointer to QpnwPhasedArrayPlot so we can access the data
  6.     SpectrogramData( QpnwPhasedArrayPlot * theParent ):
  7.         QwtRasterData(QwtDoubleRect(-90, 0, 180, 2000)) // Left, bottom, width, height
  8.     {
  9.     	parent = theParent;
  10.     }
  11. 	// Left as example
  12.     virtual QwtRasterData *copy() const
  13.     {
  14.         return new SpectrogramData(0);
  15.     }
  16. 	// Left as example
  17.     virtual QwtDoubleInterval range() const
  18.     {
  19.         return QwtDoubleInterval(0.0, 4096);
  20.     }
  21. 	// Return data. Crashes here.
  22.     virtual double value(double x, double y) const
  23.     {
  24.     	QMessageBox::information(0,"","A");
  25.     	return parent->spectData[(unsigned int) x+90].at( (unsigned int) y );
  26.     }
  27.  
  28. };
  29.  
  30.  
  31.  
  32. QpnwPhasedArrayPlot::QpnwPhasedArrayPlot(QwtPlot * thePlot)
  33. {
  34. 	DEBUG->print(QDateTime::currentDateTime().toString("dd.MM.yy hh:mm:ss.zzz") + ": " + "Initialising Plot");
  35.  
  36. 	// Create spectrogram
  37. 	spectrogram = new QwtPlotSpectrogram();
  38.  
  39. 	// Create some fake data
  40. 	for( int x = 0; x < 180; x++ )
  41. 		for( int y = 0; y < 2000; y++ )
  42. 			spectData[x].append(y);
  43. 	spectData[90].clear();
  44. 	for( int x = 0; x < 2000; x++ )
  45. 		spectData[90].append(x);
  46.  
  47. 	// Attach the data
  48.     spectrogram->setData(SpectrogramData(this));
  49. 	spectrogram->attach(thePlot);
  50. }
  51. //
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