How to change axis scale with out changing data series?

[mike_the_tv]

Ok, lets call this factor 'f'.

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

virtual QPointF YourSeriesData::sample(size_t i) const
{
    return QPointF( f * toFFTbin(i), m_data[i]); // do your scaling here
}

virtual QPointF YourSeriesData::sample(size_t i) const
{
    return QPointF( f * toFFTbin(i), m_data[i]); // do your scaling here
}

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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.