CODEWITHSUNDEEP
phparraysmultidimensional-array
Tedxxxx
Tedxxxx

Reputation: 258

Combine 2 arrays into 2d array without losing data

I have 2 arrays and want to combine into third array with one array as key and another as value. I tried to use array_combine(), but the function will eliminate all the repeated keys, so I want the result array as a 2d array. The sample array is as below: 

$keys = {0,1,2,0,1,2,0,1,2};
$values = {a,b,c,d,e,f,g,h,i};
 $result = array(
    [0]=>array(0=>a,1=>b,2=>c),
    [1]=>array(0=>d,1=>e,2=>f),
    [2]=>array(0=>g,1=>h,2=>i)
 );
//What i am using right now is: 
$result = array_combine($keys,$values);

But it only returns array(0=>g,2=>h,3=>i). Any advice would be appreciated!

Upvotes: 2

Views: 125

Answers (3)

mickmackusa
mickmackusa

Reputation: 47874

As a more flexible/robust solution, push key-value pairs into new rows whenever the key's value is already in the currently targeted row. In other words, there will never be an attempt to write a key into a row that already contains that particular key.

This can be expected to be highly efficient because there are no iterated function calls ...no function calls at all, really.

Code: (Demo)

$result = [];
foreach ($keys as $i => $key) {
    $counter[$key] = ($counter[$key] ?? -1) + 1;
    $result[$counter[$key]][$key] = $values[$i];
}
var_export($result);

Upvotes: 0

Anand Pandey
Anand Pandey

Reputation: 2025

Yes the above is working and i give upvote too for this but i dont know why you combine into the foreach loop its not necessary. The results are given in only in second line. Can you describe?

<?php
 $keys = array(0,1,2,0,1,2,0,1,2);
 $values = array('a','b','c','d','e','f','g','h','i');
 $v = array_chunk($values,count(array_unique($keys)));
 echo "<pre>";print_r($v);
?>

https://eval.in/859759

Upvotes: 1

Death-is-the-real-truth
Death-is-the-real-truth

Reputation: 72299

You can do it like below:-

<?php

$keys = array(0,1,2,0,1,2,0,1,2);
$values = array('a','b','c','d','e','f','g','h','i');

$values = array_chunk($values,count(array_unique($keys)));

foreach($values as &$value){
   $value = array_combine(array_unique($keys),$value);
}

print_r($values);

https://eval.in/859753

Upvotes: 2

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