Fixing An Array

[Johnny2]

I have this multidimensional array which I'll name "original":

 

$original=

array

0 =>

array

'animal' => 'cats'

'quantity' => 1

1 =>

array

'animal' => 'dogs'

'quantity' => '1'

2 =>

array

'animal' => 'cats'

'quantity' => '3'

 

 

However, I want to merge internal arrays with the same animal to produce this new array:

 

$new=

array

0 =>

array

'animal' => 'cats'

'quantity' => 4

1 =>

array

'animal' => 'dogs'

'quantity' => '1'

 

 

I've been trying for hours, but can't figure it out.

I've tried the following code, but get "Fatal error: Unsupported operand types" (Referring to line 11).

 

1 $new = array();

2 foreach($original as $entity)

3 {

4 if(!isset($new[$entity["animal"]]))

5 {

6 $new[$entity["animal"]] = array(

7 "animal" => $entity["animal"],

8 "quantity" => 0,

9 );

10 }

11 $new[$entity["animal"]] += $entity["quantity"];

12 }

 

 

So, I don't know what I'm doing and I could really use some help from the experts.

Edited March 30, 2013 by Johnny2

[falkencreative]

Here's a fixed version:

 

<?php 

$original = array(
array('animal' => 'cats', 'quantity' => '1'),
array('animal' => 'dogs', 'quantity' => '1'),
array('animal' => 'cats', 'quantity' => '3')
);

$new = array();

foreach($original as $entity)
{
if(!isset($new[$entity["animal"]]))
{
	$new[$entity["animal"]] = array("animal" => $entity["animal"], "quantity" => 0);
}
$new[$entity["animal"]]['quantity'] += $entity["quantity"];
}

echo "<pre>";
print_r($new);
echo "</pre>";

Basically, the key thing was this line:

 

$new[$entity["animal"]]['quantity'] += $entity["quantity"];

In your original sample, you missed the "['quantity]" portion, meaning you were trying to access the entire array, not specifically the quantity key within that array. This meant you were trying to add a number to an array, and since those are incompatible types, you got an error.

 

However... this code doesn't do exactly what you want, since this is the result:

 

Array
(
   [cats] => Array
       (
           [animal] => cats
           [quantity] => 4
       )

   [dogs] => Array
       (
           [animal] => dogs
           [quantity] => 1
       )

)

Note how you have "[cats]" and "[dogs]" instead of [0] and [1]? You'll need to work on fixing that, but it's a first step in the right direction.

Edited March 30, 2013 by Ben

[Johnny2]

Thank you very much Ben!

 

The fixed worked well. I figured out the rest from there.

 

Sorry it took so long to respond. I believe I got distracted when I last read your feedback.