Count number of occurrences of value in a PHP array

Question

I have loaded the results of an SQL query into an array. The fields are ComputerName, time_in_days, room, keyed on ComputerName.

I would like to find out how many times each time_in_days occurrence happens.

Example values of array are:

[STU-CZC1087SNC] => Array
    (
        [ComputerName] => STU-CZC1087SNC
        [time_in_days] => 0
        [room] => 4Q08
    )

[STU-CZC02501QT] => Array
    (
        [ComputerName] => STU-CZC02501QT
        [time_in_days] => 12
        [room] => 2R017
    )

So I want to know how many computers have time_in_days = 12, and how many have time_in_days = 0 for example.

It will be used to plot a graph.

How do I do / what is the best way of doing this?

score 2 · Answer 1 · answered Mar 06 '14 at 14:04

2

$result = count(
    array_filter(
        $myArray,
        function($value) {
            return $value['time_in_days'] == 12;
        }
    )
);

answered Mar 06 '14 at 14:04

Mark Baker

209,507
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385

**+1** Mark.. Took me a lil while to understand :) – Shankar Narayana Damodaran Mar 06 '14 at 14:12
I dont't think this is the generic solution the OP is asking for. This does not work when there are arbitrary numbers in the computer data. Like time_in_days=15 and time_in_days=2 etc etc. – Kapitein Witbaard Mar 06 '14 at 14:13
@MarkBaker Please improve this code-only answer with a bit of explanation. – mickmackusa Oct 20 '17 at 21:43

score 1 · Accepted Answer · answered Mar 06 '14 at 14:03

1

Try this, where $input is your array of arrays with the computer data:

$result = array();
foreach($input as $computerName => $arr){
  if(!isset($result[ $arr['time_in_days'] ]))
    $result[ $arr['time_in_days'] ] = 0;
  $result[ $arr['time_in_days'] ]++;
}
return $result;

The result will be something like:

[
  12 => 2, //2 computers have time_in_days of 12
  0 => 1  //1 computer has time_in_days of 0
]

answered Mar 06 '14 at 14:03

Kapitein Witbaard

998
9
18

I would recommend an if/else because when your `if` is `true`, you write to `0` then immediately overwrite to `1`. More logical to use `if(...){...=1}else{++}` – mickmackusa Oct 20 '17 at 22:02
I really prefer it this way. It's in my opinion better readable/understandable code: always increment by one. And functionally separated: if its not set, then initialize the value. – Kapitein Witbaard Oct 23 '17 at 14:18

score 0 · Answer 3 · answered Mar 06 '14 at 14:10

OK, here's the working example:

<?php

$computerarray = [
'STU-CZC1087SNC' => Array
(
    'ComputerName' => 'STU-CZC1087SNC',
    'time_in_days' => 0,
    'room' => '4Q08'
),

'STU-CZC02501QT' => Array
(
    'ComputerName' => 'STU-CZC02501QT',
    'time_in_days' => 12,
    'room' => '2R017'
),
'STU-CZC02501QF' => Array
(
    'ComputerName' => 'STU-CZC02501QT',
    'time_in_days' => 12,
    'room' => '2R017'
)    
];


$myarray = array();
foreach($computerarray as $key => $val){
    $myarray[] = $val['time_in_days'];
}

echo "<pre>";
$myarray = array_count_values($myarray);
print_r($myarray);

score 0 · Answer 4 · answered Mar 06 '14 at 14:18

0

This should work -

$my_arr = Array();
array_walk($arr, function($v) use(&$my_arr) {$my_arr[] = $v['time_in_days'];});
$time_freq = array_count_values($my_arr);
var_dump($time_freq);
/**
  OUTPUT
**/
array
  0 => int 1
  12 => int 2

answered Mar 06 '14 at 14:18

Kamehameha

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A short bit of explanation with this code-only answer will benefit future SO readers. – mickmackusa Oct 20 '17 at 21:43

score 0 · Answer 5 · answered Oct 30 '17 at 08:07

I'll remove my comment on the question that says:

The best way to do this is to not use php, but sql to GROUP BY time_in_days and call COUNT(). Here's a push in the right direction.

As for a conditional-less, functional approach, here is a one-liner using the two functions that were specifically designed for this task: array_count_values() and array_column()

Code: (Demo)

$computerarray = [
    'STU-CZC1087SNC' => ['ComputerName' => 'STU-CZC1087SNC','time_in_days' => 0,'room' => '4Q08'],
    'STU-CZC02501QT' => ['ComputerName' => 'STU-CZC02501QT','time_in_days' => 12,'room' => '2R017'],
    'STU-CZC02501QF' => ['ComputerName' => 'STU-CZC02501QT','time_in_days' => 12,'room' => '2R017']    
];

var_export(array_count_values(array_column($computerarray,'time_in_days')));

Output:

array (
  0 => 1,
  12 => 2,
)

score -1 · Answer 6 · answered Mar 06 '14 at 14:01

-1

Maybe array_count_values, see manual: http://pl1.php.net/array_count_values

answered Mar 06 '14 at 14:01

hopsoo

305
1
3

score -1 · Answer 7 · answered Mar 06 '14 at 14:04

-1

foreach($ya as $a) {
    $newarr[$a['time_in_days']]++;
}

answered Mar 06 '14 at 14:04

zogby

462
4
15

Almost the same as my answer, you will get lot's of notices with this code. Just add error_reporting(0); to prevent those? ;-P – Kapitein Witbaard Mar 06 '14 at 14:07

score -1 · Answer 8 · edited Oct 20 '17 at 21:46

-1

$total = null; 
foreach ($members as $owner): 
    if($owner['circle_id'] == $c['id']): // or if($owner['circle_id'] == 1):
        $total = $total + 1;
    endif;
endforeach;
echo $total;

This code calculates the number of members within a circle. It matches the members Table id with the current circle id. Its current value is $c['id'] = 1

edited Oct 20 '17 at 21:46

mickmackusa

43,625
12
83
136

answered Mar 06 '14 at 14:14

user3043185

9
2

Count number of occurrences of value in a PHP array

8 Answers8