Sum of array values where key is greater than certain value

Question

In PHP, How do you sum the values of an array where the key is greater than a number (e.g., 20)?

Note: Both keys are values are numeric.

jondavidjohn · Accepted Answer · 2011-07-05 20:16:34Z

8

$sum = 0;

foreach ($array as $key => $value)
{
    if ($key > 20)
        $sum += $value;
}

answered Jul 5, 2011 at 20:16

jondavidjohn

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Comments

Chriszuma · Accepted Answer · 2011-07-05 20:17:32Z

2

$sum = 0;
foreach( $array as $key => $value ){
  if( $key > 20 )
    $sum += $value;
}

answered Jul 5, 2011 at 20:17

Chriszuma

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kongr45gpen · Accepted Answer · 2011-07-05 20:17:26Z

0

<?php
$arr = array(...);
$n = 0;
foreach($arr as $an => $a) {
    if($an > 20) {
        $n += $a;
    }
}
echo $n;
?>

answered Jul 5, 2011 at 20:17

kongr45gpen

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Emre Yazici · Accepted Answer · 2011-07-05 20:18:58Z

0

You can start your loop from your start key:

$sum = 0;
$keyStart = 20;
for($i = $keyStart, $c = count($array); $i < $c; $i++) {
    $sum += $arr[$i];
}

Please note that I assume that your array is numerically indexed and array keys are continuous here.

answered Jul 5, 2011 at 20:18

Emre Yazici

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