array_max_ext (and similar for other array functions)

[Appsurdgames]

The function array_max (already implemented) returns the maximum value in the array.
It would make sense to offer array_max_ext which does the exact same thing,
but returns an array containing the maximum value as first entry and the index of this value as second entry.

A similar extension is possible for array_min, array_mean, array_sum and array_median.

Here is a possible implementation:

/// @param {array}	array	Input array
/// @return [max_value, index]

function array_max_ext(_array)
{
	if is_array(_array)
	{
		max_val = -infinity;
		index = -1;
		for(var i = 0; i<array_length(_array); i++)
		{
			if (_array[i] > max_val)
			{
				max_val = _array[i];
				index = -1;
			}
		}
		return [max_val, index];
	}
	else
	{
		return [undefined, undefined];
	}
}```

[Alphish]

I'd be wary of returning a new array for each call, as it might clutter lots of memory pretty quick, depending on the usage.

However, I wouldn't mind a function like array_max_index and its kin, which would return the first index of the max value, and could then be used to quickly retrieve the actual max value. If someone's so inclined, they could make the array_max_ext function like yours using array_max_index then.

[tabularelf]

I think I too prefer an array_max_index if anything.
I actually wonder how fast it'd be if we cobble it with array_max + array_get_index. 🤔
(Though a loop makes more logical sense IMO, just food for thought.)

[Appsurdgames]

I forgot about memory, thanks for bring that up. Then a version just returning the index would be awesome :)