<?php
    $males   = array();
    $malepersons = array();
    $females = array();
    $femalepersons = array();
    $result  = array();
 
    $values = [[
        "name" => 'Anna',
        "height" => 175,
        "weight" => 53.4,
        "gender" => 'Female'
        ],[
        "name" => 'Dan',
        "height" => 185.1,
        "weight" => 90.4,
        "gender" => 'Male'
        ] ];
 
    //Simplified for loop
    foreach ($values as $row){
        $person = array();
        $person['name'] = $row['name'];
        $person['x'] = $row['height'];
        $person['y'] = $row['weight'];
 
        if($row['gender'] == 'Male'){
            array_push($malepersons, $person);        
        } elseif($row['gender'] == 'Female') {
            array_push($femalepersons, $person);
        }
    }
 
    //took these out of the for loop, only need to be set once
    $males['color'] = 'black'; 
    $males['name'] = 'Male';
    $males['data'] = $malepersons;
    $females['color'] = 'green';
    $females['name'] = 'Female';
    $females['data'] = $femalepersons;
 
 
    array_push($result, $males);
    array_push($result, $females);
    print json_encode($result, JSON_NUMERIC_CHECK);
    ?>

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