如何将php数组的元素相乘

Question

I'm trying to translate a javascript function into php but having some problems with my arrays. I need to iterate over the array elements, multiplying them all by a certain amount, but it's not changing the values. Pretty sure it's because my syntax $coordinates_p[i][0] *= $scale; isn't correct, but I'm not sure what it should be!

Test code:

<?php

print "Starting.<br/>";

$scale = 100;

$coordinates_p = array();

$i = 0;
$x_coordinate = 1;
$y_coordinate = 2;
while ($i <= 1) {
    $coordinates_p[$i] = array(0 => $x_coordinate, 1 => $y_coordinate);
    $x_coordinate += 1;
    $y_coordinate += 2;
    $i++;
}

print "Unscaled: ";
print_r ($coordinates_p);
print "<br/>";

$i = 0;
while (isset($coordinates_p[i])) {
    $coordinates_p[i][0] *= $scale;
    $coordinates_p[i][1] *= $scale;
    $i++;
}

print "Scaled: ";
print_r ($coordinates_p);
print "<br/>";

print "Finished.";

?>

Answer 1

Your code just needs to change from

$coordinates_p[i][0] *= $scale;
$coordinates_p[i][1] *= $scale;

to

$coordinates_p[$i][0] *= $scale;
$coordinates_p[$i][1] *= $scale;