Standard deviation of a list
list, python, standard-deviation
Solution
Since Python 3.4 / PEP450 there is a `statistics module` in the standard library, which has a method `stdev` for calculating the standard deviation of iterables like yours:
>>> A_rank = [0.8, 0.4, 1.2, 3.7, 2.6, 5.8]
>>> import statistics
>>> statistics.stdev(A_rank)
2.0634114147853952
Problem
I want to find mean and standard deviation of 1st, 2nd,... digits of several (Z) lists. For example, I have ``` A_rank=[0.8,0.4,1.2,3.7,2.6,5.8] B_rank=[0.1,2.8,3.7,2.6,5,3.4] C_Rank=[1.2,3.4,0.5,0.1,2.5,6.1] # etc (up to Z_rank )... ``` Now I want to take the mean and std of `*_Rank[0]`, the mean and std of `*_Rank[1]`, etc. (ie: mean and std of the 1st digit from all the (A..Z)_rank lists; the mean and std of the 2nd digit from all the (A..Z)_rank lists; the mean and std of the 3rd digit...; etc).