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Detrending Data in Python with Numpy
June 24th, 2010

Detrending Data in Python with Numpy

While continuing my quest into the world of linear data analysis and signal processing, I came to a point where I wanted to emphasize variations in FFT traces. While I am keeping my original data for scientific reference, visually I want to represent it emphasizing variations rather than concentrating on trends. I wrote a detrending function which I'm sure will be useful for many applications:

def detrend(data,degree=10):
 for i in range(degree,len(data)-degree):
 return detrended+[None]*degree

However, this method is extremely slow. I need to think of a way to accomplish this same thing much faster. [ponders]

UPDATE: It looks like I've once again re-invented the wheel. All of this has been done already, and FAR more efficiently I might add. For more see scipy.signal.detrend.html

import scipy.signal
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