在多维数组中添加列的所有给定值的更简单方法是什么？

Question

I feel like there must be an easier way to handle this problem; so I have a multidimensional array like this:

$reports = array(
    array("Complete Installation", 1),
    array("Register + OSR Install", 0),
    array("OSR + Wire", 0),
    array("OSR Only", 1),
    array("Ground Strap Installation", 2),
    array("Meter Only", 2)
);

And I would like to show a percentage out of the total value of the second (well, first, but you know what I mean) column of the Array. Right now I'm using a foreach, but it seems really redundant and not very efficient:

foreach($reports as $report) {
    $total_val += (int)$report[1];
}
foreach($reports as $report) {
    $name = $report[0];
    $val = (int)$report[1];
?>
<tr>
    <td><?=(stripslashes($name));?></td>
    <td><?=($val);?></td>
    <td><?=(($val > 0) ? round(($val / $total_val) * 100, 2) : $val);?></td>
</tr>

I feel like there must be a better way to handle that, in-order to get the variable $total_val = 6; without re-looping the Array. A way to add up all the $report[1]'s. Any ideas?

Answer 1

If you run PHP 5.5 it's dead easy:

$total = array_sum(array_column($reports, 1));

If you don't, then either the foreach (there is nothing wrong with it -- on the contrary, simple is good) or some fancy alternatives:

// If you go fancy this should be your choice, the others are slightly inferior
$total = array_reduce($reports, function($sum, $r) { return $sum + $r[1]; }, 0);

or

$total = array_sum(array_map(function($r) { return $r[1]; }, $reports);

or

$total = 0;
array_walk($reports, function($r) use (&$total) { $total += $r[1]; });