Quote Originally Posted by Uwe View Post
Ok, lets call this factor 'f'.

Assuming you have your values in m_data, what is an array of doubles:

Qt Code:
  1. virtual QPointF YourSeriesData::sample(size_t i) const
  2. {
  3. return QPointF( f * toFFTbin(i), m_data[i]); // do your scaling here
  4. }
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Uwe
Now I see how it works. Sorry for being such an idiot. The answer was right there in front of my own eyes. The sample() function does not just return the y value but the x as well, and I can modify the x value to convert my 0-1024 to 0-500MHz.

Thanks for the being so patient.