stats_standard_deviation

Returns the standard deviation

Description

float stats_standard_deviation(array $a, bool $sample = false)

Returns the standard deviation of the values in a.

Parameters

a

The array of data to find the standard deviation for. Note that all values of the array will be cast to float.

sample

Indicates if a represents a sample of the population; defaults to false.

Return Values

Returns the standard deviation on success; false on failure.

Errors/Exceptions

Raises an E_WARNING when there are fewer than 2 values in a.