You can calculate the median of an array of numbers in PHP in the following steps:

- Sort the array in ascending order;
- Determine the median, which would be
*one*of the following:- Element at the middle index if the array has an odd number of elements, or;
- Average of the two elements at the middle indexes if the array has an even number of elements.

For example, you can implement this in the following way:

function median(array $arr): float|int { // 1: sort array in ascending order sort($arr); $totalArrElems = count($arr); $middleIndex = $totalArrElems / 2; // 2.1: if odd, return middle element if ($totalArrElems % 2 !== 0) { return $arr[floor($middleIndex)]; } // 2.2: if even, return average of two middle elements return ($arr[$middleIndex - 1] + $arr[$middleIndex]) / 2; }

For arrays with an odd length, rounding down the middle index (i.e. `floor($middleIndex)`

is needed because dividing an odd array length by `2`

would result in a fraction.

For example, using this function you can calculate the median of an array of numbers in the following way:

var_dump(median([1, 2])); // 1.5 var_dump(median([4, 1, 7])); // 4 var_dump(median([3, 7, 5, 1, 8, 9])); // 6 var_dump(median([39, 3, 14, 29, 23, 13, 23, 23, 40, 23, 21, 5, 7, 12, 56])); // 23

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