how to make min and max values of spectrogram dynamical?

[Uwe]

The range is something, that has to correspond to the color map - but it has nothing to do with the current min/max values of your data set in specific area. But even if you want to have it this way calculating it in QwtRasterData::value is completely the wrong place.

But your main problem is, that you insist on not trying to understand what you are doing. With this attitude you can't be surprised, that nobody answers to your postings anymore.

Uwe

[rambo83]

I know that the range corresponds to the colormap. This is exactly the reason why I want it to be dynamical. Otherwise, I have to determine the possible range by plotting the function in Matlab and see what is the global minimum and maximum.

I could certainly calculate the min and max range by iterating through x1 and x2 space and determine the range in that way, but then I would have to use 2 FOR loops, which would be very time consuming. Therefore, I had the idea to calculate it within the function "value()" because there all values are calculated anyway. Unfortunately, it is not that easy, as I thought.

@Uwe: How to learn, if nobody answers my questions? ;-)