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trader_stddev

(PECL trader >= 0.2.0)

trader_stddev — Standard Deviation

说明

trader_stddev ( array $real [, int $timePeriod [, float $nbDev ]] ) : array

参数

real

浮点数数组。

timePeriod

Number of period. Valid range from 2 to 100000.

nbDev

返回值

Returns an array with calculated data or false on failure.