Calculating standard deviation of a sample

Question

This looks a bit confusing. When you need to calculate the std, you can easily use np.std(). And Std is square root of variance. However, when we calculate variance of a sample, we divide it by n-1. So if we use np.std() this shouldn't give us a correct output.

Is there another way to calculate standard deviation of a sample or do we need to calculate it manually?

Answer 1

You can specify the denominator degrees of freedom when you use np.std(). Just use the ddof parameter:

np.std(x, ddof=1)

You can read more about it in the docs