stats_harmonic_mean

(PECL stats >= 1.0.0)

stats_harmonic_mean — 値の配列の調和平均を返す

説明

number stats_harmonic_mean ( array $a )

警告

この関数は、現在のところ詳細な情報はありません。引数のリストのみが記述されています。

パラメータ

a

返り値

add a note User Contributed Notes stats_harmonic_mean

Daniel Morris (www.danielxmorris.com) 15-Aug-2008 01:51


I wrote this to calculate harmonic averages in my shares program.  Hopefully this can help someone who doesn't want to use PECL.  The function accepts an unlimited number of arguments without the need to place them into an array, which is better than the way the PECL extension handles the function.



<?php



/**

 *  @author    Daniel Morris

*/

function harmonic () {

    $num_args = func_num_args ();

    for ($i = 0; $i < $num_args; $i++) {

        $sum += 1 / func_get_arg ($i);

    }

    return $num_args / $sum;

}



// Tests



echo harmonic (1, 2, 3, 4, 5);

echo harmonic (-1, 3, 4, 10293);

echo harmonic (-1, -2, -3, -4, -5);



//  2.1897810218978

//  -9.6022389365052

//  -2.1897810218978  



?>

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