php array_count_valuesで配列内の少数の値をカウントする

array_combine(配列, 配列)

<?php

$arr = [1.11, 1.11, 2.222, 2.222, 3.3];

$result = array_count_values($arr);

print_r($result);


<出力結果>
PHP Warning:  array_count_values(): Can only count string and integer values, entry skipped in

<?php

$arr = [1.11, 1.11, 2.222, 2.222, 3.3];

$arr = array_map(fn ($x) => (string)$x, $arr);

$result = array_count_values($arr);

print_r($result);

Array
(
    [1.11] => 2
    [2.222] => 2
    [3.3] => 1
)