Finding the minimum value's key in an associative array

Question

In PHP, say that you have an associative array like this:

$pets = array(
    "cats" => 1,
    "dogs" => 2,
    "fish" => 3
);

How would I find the key with the lowest value? Here, I'd be looking for cats.

Is there some built in PHP function that I've missed which does this? It would also be great if there was a solution that accounted for several values being identical, as below:

$pets = array(
    "cats" => 1,
    "dogs" => 1,
    "fish" => 2
);

Above, I wouldn't mind if it just output either; cats or dogs.

Thanks in advance.

Answer 1

array_keys is your friend:

$pets = array(
    "cats" => 1,
    "dogs" => 2,
    "fish" => 3
);
array_keys($pets, min($pets));  # array('cats')

P.S.: there is a dup here somewhere on SO (it had max instead of min, but I can distinctly remember it).

Answer 2

Thats how i did it.

$pets = array(
    "cats" => 1,
    "dogs" => 2,
    "fish" => 3
);

array_search(min($pets), $pets); 

I hope that helps

Answer 3

Might try looking into these:

• natcasesort(array)
• natsort(array)

Answer 4

$min_val = null;
$min_key = null;
foreach($pets as $pet => $val) {
  if ($val < $min_val) {
    $min_val = $min;
    $min_key = $key;
  }
}

You can also flip the array and sort it by key:

$flipped = array_flip($pets);
ksort($flipped);

Then the first key is the minimum, and its value is the key in the original array.

Answer 5

find the highest value

print max(120, 7, 8, 50);

returns --> 120

$array = array(100, 7, 8, 50, 155, 78);
print max($array);

returns --> 155

find the lowest value

print min(120, 7, 8, 50);

returns --> 7

$array = array(50, 7, 8, 101, 5, 78);
print min($array);

returns --> 5