Fourier transform of a Gaussian is not a Gaussian, but thats wrong! - Python

Question

I am trying to utilize Numpy\'s fft function, however when I give the function a simple gausian function the fft of that gausian function is not a gausian, its close but its

Answer 1

It is being displayed with the center (i.e. mean) at coefficient index zero. That is why it appears that the right half is on the left, and vice versa.

EDIT: Explore the following code:

import scipy
import scipy.signal as sig
import pylab
x = sig.gaussian(2048, 10)
X = scipy.absolute(scipy.fft(x))
pylab.plot(x)
pylab.plot(X)
pylab.plot(X[range(1024, 2048)+range(0, 1024)])

The last line will plot X starting from the center of the vector, then wrap around to the beginning.