pyFAI
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silx-kit
standard deviation (std) vs standard error to the mean (sem)
PyFAI is actually reporting the standard error to the mean which is roughly sqrt(sum(variance))/count while the standard deviation is sqrt(sum(variance)/count). There is sqrt(count) difference which correspond to error of the mean (reported) or the error of one pixel (not reported)
The bug is that in all the docs, code and docstrings, this is called std or sigma and both are wrong.
I suggest to use sigma_p for the standard deviation (error of one pixel) and sigma_m for the standard error of the mean. But of course this will take ages to correct all the code and have everything consistent !
