[SciPy-User] Does/how does ifft expect frequencies (on x-axis)?

[Matti Viljamaa]

I was trying to ifft a filter magnitude response that’s simply drawn into an array of filter length, e.g. 64 samples.
So I have the array of 64 samples and this obviously means that the x-axis is in samples, not frequencies.

ifft:ing this array does give me something that looks like the impulse response, but I didn’t give ifft any frequency data, just samples 0-64 in the x-axis. What I think I could’ve done is rather specify the magnitude response in 2D array or something so that the frequency runs from [0.0, 1.0] (0.5 corresponding to the Nyquist frequency) and then specify the magnitudes in 64 samples evenly spread on [0.0, 1.0], which is what I _intend_ with my array.

So does ifft expect frequencies somehow or does it also work in the way that I used it, i.e. that the frequency response going into it is in samples rather than in frequencies?

The functions I’m interested are any ifft in SciPy.