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stats_variance

(PECL stats >= 1.0.0)

stats_variance — Returns the variance

说明

stats_variance(array $a, bool $sample = false): float

Returns the variance of the values in a.

参数

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.

返回值

Returns the variance on success; false on failure.