从数组PHP中删除负整数[重复]

I'm trying to remove all negative integers from the following array :

$array = array([-122,121,-124,124,-121,122,-122,124,-121,124,-122,125,-121,121,-123,122,-124,120]);

I've tried the following, it's not working as I don't really understand how array_filter works :

function positive($var) {
  if ($var >= 0) {
    return $var;
  }
}

print_r(array_filter($array, positive($var)));

How would I send each value to the positive function? Or is there a better way of doing this? array_walk or array_map maybe?

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Use this code:

<?php
$array = array([-122,121,-124,124,-121,122,-122,124,-121,124,-122,125,-121,121,-123,122,-124,120]);

function positive($var) 
{
    if ($var >= 0) 
    {
        return true;
    }
}

print_r(array_filter($array[0], 'positive'));

You had to pass $array[0] as parameter to modify array. You have declared array with array in first element array([-122,...,-124,120]); so to filter array you need to pass $array[0].

Output is:

Array ( [1] => 121 [3] => 124 [5] => 122 [7] => 124 [9] => 124 [11] => 125 [13] => 121 [15] => 122 [17] => 120 )

The PHP Documentation states:

array array_filter ( array $array [, callable $callback [, int $flag = 0 ]] )

Iterates over each value in the array passing them to the callback function. If the callback function returns true, the current value from array is returned into the result array. Array keys are preserved.

Use a callback that tests for a positive value:

$array = [-122,121,-124,124,-121,122,-122,124,-121,124,-122,125,-121,121,-123,122,-124,120];
$positive_integers = array_filter($array, function($value) {
    return $value > 0;
});