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Re: gsl_histogram_sum proposal


Achim Gaedke writes:
 >  That is a good reason - on the other hand the pdf functions have
 > quite similar mechansims. The cumulative probability aspect - this
 > is a scientific argument - is hit here and its my initention for
 > implementing slices of the total sum. 

I think the relevant quantities here are the P(x) and Q(x) functions
of the PDF.  Functions to compute those would make sense. e.g.

double gsl_histogram_pdf_P (gsl_histogram_pdf *p, double x)

 >  I can schedule this for next week. Are there hints/ideas for
 > numeric implementation (references, literature)?

The mean and sigmas should be a straightforward generalisation of
stat.c to two variables x, y.  For the cross correlation use
r=<(x-<x>)(y-<y>)>/(sigma_x*sigma_y) where <.> is the weighted mean.

-- 
Brian

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