PHPのお勉強！

PHP TOP
PHP 8.4.2 Released!

    array_count_values

    (PHP 4, PHP 5, PHP 7, PHP 8)

    array_count_values — 配列内に存在する、異なる値の出現回数を数える

    説明

    array_count_values(array $array): array

    array_count_values() は、 配列 array の値 (数値または文字列でなければいけません) をキーとし、 array におけるその値の出現回数を値とした配列を返します。

    パラメータ

    array

    値を数える配列。

    戻り値

    array のキーとその登場回数を組み合わせた連想配列を返します。

    エラー / 例外

    string あるいは int 以外の型の要素が登場するたびに E_WARNING が発生します。

    例

    例1 array_count_values() の例

    <?php
    $array     = array(1, "hello", 1, "world", "hello");
    print_r(array_count_values($array));
    ?>

    上の例の出力は以下となります。

    Array
(
    [1] => 2
    [hello] => 2
    [world] => 1
)

    参考

    • count() - 配列または Countable オブジェクトに含まれるすべての要素の数を数える
    • array_unique() - 配列から重複した値を削除する
    • array_values() - 配列の全ての値を返す
    • count_chars() - 文字列で使用されている文字に関する情報を返す

    Found A Problem?

    Learn How To Improve This Page • Submit a Pull Request • Report a Bug
    ＋add a note

    User Contributed Notes 3 notes

    up
    27
    sergolucky96 at gmail dot com
    7 years ago
    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
    ?>
    up
    7
    rabies dot dostojevski at gmail dot com
    17 years ago
    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.
    up
    6
    szczepan.krolgmail.c0m
    14 years ago
    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
    )
    */
    ?>
    ＋add a note