# atoti.agg.std module#

atoti.agg.std(operand: NonConstantColumnConvertibleOrLevel, /, *, mode: Literal['sample', 'population'] = 'sample') MeasureDescription#
atoti.agg.std(operand: NonConstantMeasureConvertible, /, *, mode: Literal['sample', 'population'] = 'sample', scope: Scope) MeasureDescription

Return a measure equal to the standard deviation of the passed operand across the specified scope.

Parameters
• operand – The operand to get the standard deviation of.

• mode

One of the supported modes:

• The sample standard deviation, similar to Excel’s STDEV.S, is $$\sqrt{\frac{\sum_{i=1}^{n} (X_i - m)^{2}}{n - 1}}$$ 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 $$\sqrt{\frac{\sum_{i=1}^{n}(X_i - m)^{2}}{n}}$$ 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.

• scope – The scope of the aggregation.