[Numpy-discussion] Newbie Installation problems

Chris Barker chrishbarker at home.net
Tue Aug 28 12:40:10 CDT 2001


Charles G Waldman wrote:

> I think there are some statistics modules floating around on the Net,
> but mean and standard deviation are one-liners in NumPy:
> 
> from Numeric import *
> 
> def mean(a):
>     return float(sum(a))/len(a)
> 
> def std_dev(a):
>     return sqrt(mean((a-mean(a))**2))

or, for the unbiased estimate:

def std_dev(a):
    return sqrt(sum((a-mean(a))**2)/(len(a)-1))

You can also find these in Mlab.py

-Chris

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Christopher Barker,
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