(PHP 4, PHP 5, PHP 7, PHP 8)
array_count_values — Counts the occurrences of each distinct value in an array
array_count_values() returns an array using
the values of array (which must be ints or strings) as keys and
their frequency in array as values.
arrayThe array of values to count
Returns an associative array of values from array as
keys and their count as value.
Example #1 array_count_values() example
<?php
$array = array(1, "hello", 1, "world", "hello");
print_r(array_count_values($array));
?>The above example will output:
Array
(
[1] => 2
[hello] => 2
[world] => 1
)
Simple way to find number of items with specific values in multidimensional array:
<?php
$list = [
['id' => 1, 'userId' => 5],
['id' => 2, 'userId' => 5],
['id' => 3, 'userId' => 6],
];
$userId = 5;
echo array_count_values(array_column($list, 'userId'))[$userId]; // outputs: 2
?>Here is a Version with one or more arrays, which have similar values in it:
Use $lower=true/false to ignore/set case Sensitiv.
<?php
$ar1[] = array("red","green","yellow","blue");
$ar1[] = array("green","yellow","brown","red","white","yellow");
$ar1[] = array("red","green","brown","blue","black","yellow");
#$ar1= array("red","green","brown","blue","black","red","green"); // Possible with one or multiple Array
$res = array_icount_values ($ar1);
print_r($res);
function array_icount_values($arr,$lower=true) {
$arr2=array();
if(!is_array($arr['0'])){$arr=array($arr);}
foreach($arr as $k=> $v){
foreach($v as $v2){
if($lower==true) {$v2=strtolower($v2);}
if(!isset($arr2[$v2])){
$arr2[$v2]=1;
}else{
$arr2[$v2]++;
}
}
}
return $arr2;
}
/*
Will print:
Array
(
[red] => 3
[green] => 3
[yellow] => 4
[blue] => 2
[brown] => 2
[white] => 1
[black] => 1
)
*/
?>I couldn't find a function for counting the values with case-insensitive matching, so I wrote a quick and dirty solution myself:
<pre><?php
function array_icount_values($array) {
$ret_array = array();
foreach($array as $value) {
foreach($ret_array as $key2 => $value2) {
if(strtolower($key2) == strtolower($value)) {
$ret_array[$key2]++;
continue 2;
}
}
$ret_array[$value] = 1;
}
return $ret_array;
}
$ar = array('J. Karjalainen', 'J. Karjalainen', 60, '60', 'J. Karjalainen', 'j. karjalainen', 'Fastway', 'FASTWAY', 'Fastway', 'fastway', 'YUP');
$ar2 = array_count_values($ar); // Normal matching
$ar = array_icount_values($ar); // Case-insensitive matching
print_r($ar2);
print_r($ar);
?></pre>
This prints:
Array
(
[J. Karjalainen] => 3
[60] => 2
[j. karjalainen] => 1
[Fastway] => 2
[FASTWAY] => 1
[fastway] => 1
[YUP] => 1
)
Array
(
[J. Karjalainen] => 4
[60] => 2
[Fastway] => 4
[YUP] => 1
)
I don't know how efficient it is, but it seems to work. Needed this function in one of my scripts and thought I would share it.array_count_values function does not work on multidimentional arrays.
If $score[][] is a bidimentional array, the command
"array_count_values ($score)" return the error message "Warning: Can only count STRING and INTEGER values!".A cleaner way to use array_count_values() to find boolean counts.
<?php
$list = [
['id' => 1, 'result' => true],
['id' => 2, 'result' => true],
['id' => 3, 'result' => false],
];
$result = true;
echo array_count_values(array_map('intval', array_column($list, 'result')))[(int)$result];
// outputs: 2
?>Based on sergolucky96 suggestion
Simple way to find number of items with specific *boolean* values in multidimensional array:
<?php
$list = [
['id' => 1, 'result' => true],
['id' => 2, 'result' => true],
['id' => 3, 'result' => false],
];
$result = true;
echo array_count_values(array_map(function($v) {return $v?'true':'false';},array_column($list, 'result')))[$result]
// outputs: 2
?>The case-insensitive version:
<?php
function array_count_values_ci($array) {
$newArray = array();
foreach ($array as $values) {
if (!array_key_exists(strtolower($values), $newArray)) {
$newArray[strtolower($values)] = 0;
}
$newArray[strtolower($values)] += 1;
}
return $newArray;
}
?>If you have a multidimensional array with unknown dimensions, you cannot use this function, use instead:
<?php
function array_count_recursive(array $arr): array {
$occurrences = [] ;
array_walk_recursive( $arr, function($value, $key) use (&$occurrences) {
@ $occurrences[$value]++;
// @ to surpress warnings "Undefined array key". In php8 you can also use
// $occurrences[$value] = ($occurrences[$value] ?? 0) + 1
});
return $occurrences;
}
?>