PHP - Retrieve min() object from multidimentional object array - php

Question

** EDIT ** What would happen if I only used arrays, e.g.
array(
array('name' => 'bla', 'distance' => '123');
array('name' => 'b123a', 'distance' => '1234214');
);
Would this be easier to find the min value ?
Hi there I'm trying to retrieve the object which has the lowest distance value from an array of objects. This is my data set below;
[0] => myObjectThing Object
(
[name:myObjectThing:private] => asadasd
[distance:myObjectThinge:private] => 0.9826368952306
)
[1] => myObjectThing Object
(
[name:myObjectThing:private] => 214gerwert24
[distance:myObjectThinge:private] => 1.5212312547306
)
[2] => myObjectThing Object
(
[name:myObjectThing:private] => abc123
[distance:myObjectThinge:private] => 0.0000368952306
)
So I'd like to be able to retieve the object which has the smallest distance value. In this case it would be object with name: abc123

Answer 1

Hmm for PHP >= 5.3 I would try something like this:
$Object = array_reduce($data,function($A,$B){
return $A->distance < $B->distance ? $A : $B;
})
For PHP < 5.3 the fillowing would suffice:
function user_defined_reduce($A,$B){
return $A->distance < $B->distance ? $A : $B;
}
$Object = array_reduce($data,"user_defined_reduce");

Answer 2

Previously suggested answers did not explain the need to include an $initial value to array_reduce(). The solution did not work because of it.
This one works for me (PHP 5.3.13):
$array = array(
array(
'name' => 'something',
'value' => 56
),
array(
'name' => 'else',
'value' => 54
),
array(
'name' => 'else',
'value' => 58
),
array(
'name' => 'else',
'value' => 78
)
);
$object = array_reduce($array, function($a, $b){
return $a['value'] < $b['value'] ? $a : $b;
}, array_shift($array));
print_r($object);
This will give me:
[0] => Array
(
[name] => else
[value] => 54
)
Whereas the previous solution gave me null. I'm assuming that PHP < 5.3 would require a similar initial value to be specified to array_reduce().

Answer 3

You can't flatten this as it isn't a plain old multi-dimensional array with just the values.
This should work:
$min = $object[0];
for ($i = 1; $i < count($object); $i++)
if ($object[$i]['distance'] < $min['distance'])
$min = $object[$i];

Answer 4

This example should give you a hint in the right direction:
<?php
$a = new stdClass();
$a->foo = 2;
$b = new stdClass();
$b->foo = 3;
$c = new stdClass();
$c->foo = 1;
$init = new stdClass();
$init->foo = 1000;
$vals = array( $a, $b, $c );
var_dump(
array_reduce(
$vals,
function ( $x, $y )
{
if ( $x->foo < $y->foo )
{
return $x;
}
else
{
return $y;
}
},
$init
)
);
?>

Answer 5

try:
$myObjectCollection = ...;
$minObject = $myObjectCollection[0]; // or reset($myObjectCollection) if you can't ensure numeric 0 index
array_walk($myObjectCollection, function($object) use ($minObject) {
$minObject = $object->distance < $minObject->distance ? $object : $minObject;
});
but from the looks of your dump. name and distance are private. So you want be able to access them from the object directly using ->. You'll need some kind of getter getDistance()

Answer 6

$objectsArray = array(...); // your objects
$distance = null;
$matchedObj = null;
foreach ( $objectsArray as $obj ) {
if ( is_null($distance) || ( $obj->distance < $distance ) ) {
$distance = $obj->distance;
$matchedObj = $obj;
}
}
var_dump($matchedObj);
AD EDIT:
If you will use arrays instead of objects, change $obj->distance to $obj['distance'].