# atoti.array.std module¶

atoti.array.std(measure, *, mode='sample')

Return a measure equal to the standard deviation of the elements of the passed array measure.

Parameters
• measure (MeasureDescription) – The measure to get the standard deviation of.

• mode (Literal[‘sample’, ‘population’]) –

One of the supported modes:

• The sample standard deviation, similar to Excel’s STDEV.S, is $$\sqrt{\frac{\sum_{i=0}^{n} (X_i - m)^{2}}{n - 1}}$$ where m is the sample mean and n the size of the sample. Use this mode if the data represents a sample of the population.

• The population standard deviation, similar to Excel’s STDEV.P is $$\sqrt{\frac{\sum_{i=0}^{n}(X_i - m)^{2}}{n}}$$ where m is the mean of the Xi elements and n the size of the population. Use this mode if the data represents the entire population.

Return type

MeasureDescription