How use array_map for order by word in php

Question

I have this two-dimensional array

array
(
    0 => array
    (
        "id_category" => 3
    , "name" => "mesa plegable"
    ),

    1 => array
    (
        "id_category" => 4
    , "name" => "cama plegable"
    ),

    2 => array
    (
        "id_category" => 5
    , "name" => "sillas plegables"
    ),

    3 => array
    (
        "id_category" => 6
    , "name" => "bicicleta plegable"
    ),

    4 => array
    (
        "id_category" => 7
    , "name" => "carpas plegables"
    ),

    5 => array
    (
        "id_category" => 8
    , "name" => "bicicleta estatica plegable"
    ),

    6 => array
    (
        "id_category" => 9
    , "name" => "bicicleta electrica plegable"
    ),

    7 => array
    (
        "id_category" => 10
    , "name" => "cinta de correr plegable"
    ),

    8 => array
    (
        "id_category" => 11
    , "name" => "carro compra plegable"
    ),

    9 => array
    (
        "id_category" => 12
    , "name" => "mesa plegable cocina"
    ),

    10 => array
    (
        "id_category" => 13
    , "name" => "puertas plegables"
    ),

    11 => array
    (
        "id_category" => 14
    , "name" => "tumbona plegable"
    ),

    12 => array
    (
        "id_category" => 15
    , "name" => "escalera plegable"
    ),

    13 => array
    (
        "id_category" => 16
    , "name" => "mesa plegable pared"
    ),

);

And I would like this result:

array (
  'mesa' => 
  array (
    0 => 'mesa plegable',
    1 => 'mesa plegable cocina',
    2 => 'mesa plegable pared',
  ),
  'cama' => 
  array (
    0 => 'cama plegable',
  ),
  'sillas' => 
  array (
    0 => 'sillas plegables',
  ),
  'bicicleta' => 
  array (
    0 => 'bicicleta plegable',
    1 => 'bicicleta estatica plegable',
    2 => 'bicicleta electrica plegable',
  ),
  'carpas' => 
  array (
    0 => 'carpas plegables',
  ),
  'cinta' => 
  array (
    0 => 'cinta de correr plegable',
  ),
  'carro' => 
  array (
    0 => 'carro compra plegable',
  ),
  'puertas' => 
  array (
    0 => 'puertas plegables',
  ),
  'tumbona' => 
  array (
    0 => 'tumbona plegable',
  ),
  'escalera' => 
  array (
    0 => 'escalera plegable',
  ),
)

I am a beginner, so there may be things that are not done this way. Please understand ;)

$write_element = '';

foreach ($original_array as $element){
 $name= explode(" ",$element['name']);
 $clean_name = $nombre_cat[0];

 $group_by_name = array_map("myfunction",$original_array,$clean_name);
}

function myfunction($original_array,$clean_name)
{
 //this is what I don't know how to do

 if $clean_name exists in $original_array push in new array to return all matches
}

I know how to run two foreach one inside the other and look for matches, but I think an array map would be faster and cleaner, right? Maybe I'm wrong about this too.

Can you help me please

So, according to you, what does `array_map()` does? Let's go step by step and solve it together. — Akhilesh B Chandran, Apr 01 '22 at 12:43
From what I have looked up array_map returns an array with new values, provided by the function created by the user. I want that when it goes through the foreach, it looks for the word in the original array and if there are matches. For example, if you search for "mesa" in the original array it should return an array with [0] => mesa plegable [1] => mesa plegable cocina [2] => mesa plegable pared — Jonatan, Apr 01 '22 at 12:57
Rather than use `array_map` I would have used `array_reduce`. Why? `array_map` is designed to give give you back an array that has the same number of entries as the input where each entry is modified by the `callback`. The `array_reduce` function is designed to return a `result` that is definitely different than the input array. It can be a value or an array, which is why I would use it for your requirement. — Ryan Vincent, Apr 01 '22 at 16:00

steven7mwesigwa · Accepted Answer · 2022-04-01T17:03:01.810

$data - represents the raw data.

$result - represents the final expected output/result.

$result = [];

array_map(function ($value) use (&$result) {
    if (!array_key_exists($key = substr($value["name"], 0, strpos($value["name"], " ")), $result)) $result[$key] = [];

    $result[$key][] = $value["name"];

}, $data);

var_export($result);

Addendum:

Alternatively, you could use array_reduce() as suggested by @ryan-vincent in a comment:

Rather than use array_map, I would have used array_reduce. Why? array_map is designed to give give you back an array that has the same number of entries as the input where each entry is modified by the callback. The array_reduce function is designed to return a result that is definitely different from the input array. It can be a value or an array, which is why I would use it for your requirement.

$result = array_reduce($data, function ($result, $value) {
    if (!array_key_exists($key = substr($value["name"], 0, strpos($value["name"], " ")), $result)) $result[$key] = [];

    $result[$key][] = $value["name"];
    return $result;

}, []);

var_export($result);

score 0 · Answer 2 · answered Apr 01 '22 at 12:53

here is my attempt

input array is $array

output array is $output

you can copy and paste this code at this online php code testing site

<?php
// assign input data
$array = [
    [
        'id_category' => 3,
        'name' => 'mesa plegable'
    ],
    [   'id_category' => 4,
        'name' => 'cama plegable'
    ],
    [
        'id_category' => 5,
        'name' => 'sillas plegables'
    ],
    [
        'id_category' => 6,
        'name' => 'bicicleta plegable'
    ], 
    [
        'id_category' => 7,
        'name' => 'carpas plegables'
    ],
    [
        'id_category' => 8,
        'name' => 'bicicleta estatica plegable'
    ],
    [
        'id_category' => 9,
        'name' => 'bicicleta electrica plegable'
    ],
    [
        'id_category' => 10,
        'name' => 'cinta de correr plegable'
    ],
    [
        'id_category' => 11,
        'name' => 'carro compra plegable'
    ],
    [
        'id_category' => 12,
        'name' => 'mesa plegable cocina'
    ],
    [
        'id_category' => 13,
        'name' => 'puertas plegables'
    ],
    [
        'id_category' => 14,
        'name' => 'tumbona plegable'
    ],
    [
        'id_category' => 15,
        'name' => 'escalera plegable'
    ],
    [
        'id_category' => 16,
        'name' => 'mesa plegable pared'
    ]
];

// get strings
$strings = [];
foreach( $array as $key => $value ){
    $strings[] = $value['name'];
}

// create group headings
$string_group_names = [];
foreach( $strings as $key => $value ){
    $string_group_names[] = explode(" ", $value)[0];    
}

// clean array to remove duplicates
$string_group_names = array_unique($string_group_names);

// create output array
$output = [];
foreach( $string_group_names as $key => $value ){
    $items = [];    
    foreach( $strings as $key2 => $value2 ){
        $isMatch = explode(' ', $value2)[0] == $value;
        if($isMatch){
            $items[] = $value2; 
        }
    }
    $output[$value] = $items;    
}

// do something with the output
var_dump($output);

Input Data

$array = [
    [
        'id_category' => 3,
        'name' => 'mesa plegable'
    ],
    [   'id_category' => 4,
        'name' => 'cama plegable'
    ],
    [
        'id_category' => 5,
        'name' => 'sillas plegables'
    ],
    [
        'id_category' => 6,
        'name' => 'bicicleta plegable'
    ], 
    [
        'id_category' => 7,
        'name' => 'carpas plegables'
    ],
    [
        'id_category' => 8,
        'name' => 'bicicleta estatica plegable'
    ],
    [
        'id_category' => 9,
        'name' => 'bicicleta electrica plegable'
    ],
    [
        'id_category' => 10,
        'name' => 'cinta de correr plegable'
    ],
    [
        'id_category' => 11,
        'name' => 'carro compra plegable'
    ],
    [
        'id_category' => 12,
        'name' => 'mesa plegable cocina'
    ],
    [
        'id_category' => 13,
        'name' => 'puertas plegables'
    ],
    [
        'id_category' => 14,
        'name' => 'tumbona plegable'
    ],
    [
        'id_category' => 15,
        'name' => 'escalera plegable'
    ],
    [
        'id_category' => 16,
        'name' => 'mesa plegable pared'
    ]
];

Output

array(10) {
  ["mesa"]=>
  array(3) {
    [0]=>
    string(13) "mesa plegable"
    [1]=>
    string(20) "mesa plegable cocina"
    [2]=>
    string(19) "mesa plegable pared"
  }
  ["cama"]=>
  array(1) {
    [0]=>
    string(13) "cama plegable"
  }
  ["sillas"]=>
  array(1) {
    [0]=>
    string(16) "sillas plegables"
  }
  ["bicicleta"]=>
  array(3) {
    [0]=>
    string(18) "bicicleta plegable"
    [1]=>
    string(27) "bicicleta estatica plegable"
    [2]=>
    string(28) "bicicleta electrica plegable"
  }
  ["carpas"]=>
  array(1) {
    [0]=>
    string(16) "carpas plegables"
  }
  ["cinta"]=>
  array(1) {
    [0]=>
    string(24) "cinta de correr plegable"
  }
  ["carro"]=>
  array(1) {
    [0]=>
    string(21) "carro compra plegable"
  }
  ["puertas"]=>
  array(1) {
    [0]=>
    string(17) "puertas plegables"
  }
  ["tumbona"]=>
  array(1) {
    [0]=>
    string(16) "tumbona plegable"
  }
  ["escalera"]=>
  array(1) {
    [0]=>
    string(17) "escalera plegable"
  }
}

@Jonatan if this works for you, please upvote and mark this as the answer. its slower than using array_map, but its easier to read and understand in my version. — Dean Van Greunen, Apr 01 '22 at 13:06

How use array_map for order by word in php

2 Answers2

Addendum:

Input Data

Output