How can I find the max attribute in an array of objects?

All examples assume that $prop is the name of an object property like value in your example:

function max_attribute_in_array($array, $prop) {    return max(array_map(function($o) use($prop) {                            return $o->$prop;                         },                         $array));}

• array_map takes each array element and returns the property of the object into a new array
• Then just return the result of max on that array

For fun, here you can pass in max or min or whatever operates on an array as the third parameter:

function calc_attribute_in_array($array, $prop, $func) {    $result = array_map(function($o) use($prop) {                            return $o->$prop;                        },                        $array);    if(function_exists($func)) {        return $func($result);    }    return false;}$max = calc_attribute_in_array($data_points, 'value', 'max');$min = calc_attribute_in_array($data_points, 'value', 'min');

If using PHP >= 7 then array_column works on objects:

function max_attribute_in_array($array, $prop) {    return max(array_column($array, $prop));}

Here is Mark Baker's array_reduce from the comments:

$result = array_reduce(function($carry, $o) use($prop) {                           $carry = max($carry, $o->$prop);                           return $carry;                       }, $array, -PHP_INT_MAX);

try this:

$point1 = new stdClass;$point1->value = 0.2;$point1->name = 'Bob';$point2 = new stdClass;$point2->value = 1.2;$point2->name = 'Dave';$point3 = new stdClass;$point3->value = 0.8;$point3->name = 'Steve';$data_points = [$point1, $point2, $point3];function max_attribute_in_array($data_points, $value='value'){    $max=0;    foreach($data_points as $point){        if($max < (float)$point->{$value}){            $max = $point->{$value};        }    }    return $max;}$max = max_attribute_in_array($data_points);var_dump($max);

response:

float 1.2