Building a new array using key IDS

Question

Using the numbers from $ids, I want to pull the data from $nuts.

So for example:

$ids = [0,3,5]; // 0 calories, 3 sugar, 5 fat

$nuts = [
    'calories' => 'cal',
    'protein' => 'pro',
    'carbohydrate' => 'car',
    'sugar' => 'sug',
    'fiber' => 'fib',
    'fat' => 'fat',
];

$returnData = [
    'calories' => 'cal',
    'sugar' => 'sug',
    'fat' => 'fat',
];

I could loop through each $ids number with a foreach(); but I'm curious to see if there is a better method than this?

$newNuts = array_values(array_flip($nuts));
foreach($ids as $i)
    $returnData[$newNuts[$i]] = $nuts[$newNuts[$i]];

Ali Gajani · Accepted Answer · 2014-05-28 23:23:23Z

2

I did some work and realized, you don't need array_flip, array_values is fine.

$num_nuts = array_values ($nuts);

for ($z=0; $z<sizeof($ids); $z++) {
 echo $num_nuts[$ids[$z]];            
 }

Just 1 more line of code, but I think it does the job. I think mine is going to be faster because the array_flip basically exchanges all keys with their associated values in an array, which is not what I am doing. It's actually one less pain.

I am simply converting the original array to a new one by index and simply looping upon it. Also, not the elegant way to use the power of PHP available to us, but works just fine. array_flip is O(n), but I think better not use it for larger data-sets.

answered May 28, 2014 at 23:23

Ali Gajani

15.1k12 gold badges64 silver badges106 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Community · Accepted Answer · 2023-11-17 19:51:26Z

0

How about a simple array_slice?

$result = array();
foreach ($ids as $i) {
    $result += array_slice($nuts, $i, 1, true);
}

No need to create a copy of the array.

edited Nov 17, 2023 at 19:51

CommunityBot

11 silver badge

answered May 28, 2014 at 23:33

iMoses

4,3471 gold badge26 silver badges40 bronze badges

Collectives™ on Stack Overflow

Building a new array using key IDS

2 Answers 2

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related