I had a similar problem and it drove me nuts... Your code looks OK. You didn't specify what the discrepancies were, but one thing to look into is whether your standard deviation is for a sample, or for the population. There is a difference. For a sample, you divide by (n-1); for a population, you divide by n (where n = the number of elements).

In reply to Re: standard deviation accuracy question by spiritway
in thread standard deviation accuracy question by Anonymous Monk

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