FFT using pylab

from pylab import *

data,timestep = 10*sin(arange(1000)*5/2.0/pi)+5*sin(arange(1000)*10/2.0/pi),0.01
han = hanning(len(data))
handata = han*data
n = len(data)*50
FFT = abs(fftshift(fft(handata,n)))
freq = fftshift(fftfreq(n,timestep))
plot(freq,2*FFT/sum(han))