array_product

说明

number array_product ( array array )

array_product() 以整数或浮点数返回一个数组中所有值的乘积。

例子 1. array_product() 例子
<?php $a = array(2, 4, 6, 8); echo "product(a) = " . array_product($a) . "\n"; ?>
上例将输出：
product(a) = 384

add a note User Contributed Notes

Andre D
08-Aug-2006 04:56


This function can be used to test if all values in an array of booleans are TRUE.



Consider:



<?php



function outbool($test)

{

    return (bool) $test;

}



$check[] = outbool(TRUE);

$check[] = outbool(1);

$check[] = outbool(FALSE);

$check[] = outbool(0);



$result = (bool) array_product($check);

// $result is set to FALSE because only two of the four values evaluated to TRUE



?>



The above is equivalent to:



<?php



$check1 = outbool(TRUE);

$check2 = outbool(1);

$check3 = outbool(FALSE);

$check4 = outbool(0);



$result = ($check1 && $check2 && $check3 && $check4);



?>



This use of array_product is especially useful when testing an indefinite number of booleans and is easy to construct in a loop.

mattyfroese at gmail dot com
06-Jan-2006 10:25


If you don't have PHP 5



$ar = array(1,2,3,4);

$t = 1;

foreach($ar as $n){

    $t *= $n;

}

echo $t; //output: 24

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