Students Position From Average

Sort your data by values : https://laravel.com/docs/5.7/collections#method-sort And then you can loop trough it, and implement a counter for the ranking.

@Vilfago i would really appreciate it if you can show me a working example. I've been at it since, have sorted the shit outta this array. Please help...

Could you provide me the output you want ? An array with a sub-array containing pin and value ? Key as rank, or value for rank?

@Vilfago i want an output like this..

array:10 [
    3101625668 => ["1st", 98.0],
    3101635921 => ["1st", 98.0],
    3913126364 => ["4th", 35.77],
    3913058204 => ["7th", 25.33],
    3101372540 => ["5th", 33.47],
    3913752741 => ["3rd", 40.0],
    3913120054 => ["9th", 20.4],
    3913998755 => ["6th", 26.67],
    3913861492 => ["8th", 25.2],
    3913881854 => ["10th", 19.8]
]

$results = collect([$array_results]);

$results_sorted = $results->sort()->reverse();

$current_rank = 1;
$number_in_position = 0;
$current_score = 100;

foreach($results_sorted as $pin => $result)
{
    if($result < $current_score){
        $current_score = $result;
        $current_rank += $number_in_position
        $number_in_position = 1;
        $output[$pin] = [$current_rank, $result];
        ++;
    }else{ //same score as the previous
        $number_in_position++;
        $output[$pin] = [$current_rank, $result];
    }
}

dd($output);

I didn't test it, I let you some job (test, debug, optimize)

    public function handle() {
        $marks = collect([3101625668 => 98.0, 3101635921 => 98.0, 3913126364 => 35.77, 3913058204 => 25.33, 3101372540 => 33.47, 3913752741 => 40.0, 3913120054 => 20.4, 3913998755 => 26.67, 3913861492 => 25.2, 3913881854 => 19.8,]);
        $avg  = $marks->avg();
        $rank = 1;

        $marks->sort()
            ->reverse()
            ->map(function ($mark, $id) use ($avg, &$rank) {
                return [
                    'dev'  => $mark - $avg,
                    'id'   => $id,
                    'mark' => $mark,
                    'rank' => $rank++,
                ];
            })
            ->dump();
        
        /* Illuminate\Support\Collection {
        array:10 [
          3101635921 => [
            "dev" => 55.736
            "id" => 3101635921
            "mark" => 98.0
            "rank" => 1
          ]
          3101625668 => [
            "dev" => 55.736
            "id" => 3101625668
            "mark" => 98.0
            "rank" => 2
          ]
          3913752741 => [
            "dev" => -2.264
            "id" => 3913752741
            "mark" => 40.0
            "rank" => 3
          ]
          3913126364 => [
            "dev" => -6.494
            "id" => 3913126364
            "mark" => 35.77
            "rank" => 4
          ]
          3101372540 => [
            "dev" => -8.794
            "id" => 3101372540
            "mark" => 33.47
            "rank" => 5
          ]
          3913998755 => [
            "dev" => -15.594
            "id" => 3913998755
            "mark" => 26.67
            "rank" => 6
          ]
          3913058204 => [
            "dev" => -16.934
            "id" => 3913058204
            "mark" => 25.33
            "rank" => 7
          ]
          3913861492 => [
            "dev" => -17.064
            "id" => 3913861492
            "mark" => 25.2
            "rank" => 8
          ]
          3913120054 => [
            "dev" => -21.864
            "id" => 3913120054
            "mark" => 20.4
            "rank" => 9
          ]
          3913881854 => [
            "dev" => -22.464
            "id" => 3913881854
            "mark" => 19.8
            "rank" => 10
          ]
        ]
        */
    }

Sorry, I missed the detail about resolving the ties. You'll have to do another pass over the collection to identify and score ties correctly.

@burlresearch thanks alot! It worked perfectly...

@Vilfago thank you as well! I appreciate

@burlresearch there is a slight issue here...

3913261052  10th    51.46
3913936730  9th             51.46

Aren't these two supposed to be 9th then the next one coming becomes 11th?

Yes... he told you he didn't do this part...

@Vilfago can you help out? At this point am tired... Please help. ???

Did you try my code? I'm tired too

@Vilfago there is an error in this

if($result < $current_score){
        $current_score = $result;
        $current_rank += $number_in_position
        $number_in_position = 1;
        $output[$pin] = [$current_rank, $result];

        ++; //What are you incrementing here?
    }

@Vilfago here is the output

array:1 [▼
  0 => array:2 [▼
    0 => 1
    1 => array:21 [▼
      3913936730 => 28.0
      3913239999 => 21.73
      3913659614 => 22.0
      3913160091 => 19.47
      3913885329 => 29.73
      3913582846 => 30.27
      3913645641 => 15.4
      3913087292 => 23.73
      3913646349 => 14.93
      3913280872 => 21.87
      3913028769 => 13.6
      3913747249 => 26.8
      3913049985 => 22.4
      3913083105 => 25.07
      3913282411 => 40.0
      3913662799 => 39.87
      3913261052 => 20.67
      3913865578 => 9.2
      3913062432 => 17.73
      3913395866 => 35.6
      3913059859 => 34.0
    ]
  ]
]

$array_results = [3101625668 => 98.0, 3101635921 => 98.0, 3913126364 => 35.77, 3913058204 => 25.33, 3101372540 => 33.47, 3913752741 => 40.0, 3913120054 => 20.4, 3913998755 => 26.67, 3913861492 => 25.2, 3913881854 => 19.8,];
        
        $results = collect($array_results);

        $results_sorted = $results->sort()->reverse();

        $current_rank = 1;
        $number_in_position = 0;

        $max_score = 100;
        $current_score = $max_score;

        foreach($results_sorted as $pin => $result)
        {
                if($result < $current_score ){
                        $current_score = $result;
                        $current_rank += $number_in_position;
                        $number_in_position = 1;
                        $output[$pin] = [$current_rank, $result];
                }else{ //same score as the previous
                        $number_in_position++;
                        $output[$pin] = [$current_rank, $result];
                }
        }

        dd($output);

@Vilfago thank you so very much dude! You a life saver! You should be in the first aid kit!

Just for the record, here is a minor variation that does the ranking (with ties) in a single pass. Quite simple:

public function handle() {
    $marks = collect([3101625668 => 98.0, 3101635921 => 98.0, 3913126364 => 35.77, 3913058204 => 25.33, 3101372540 => 33.47, 3913752741 => 40.0, 3913120054 => 20.4, 3913998755 => 26.67, 3913861492 => 25.2, 3913881854 => 19.8,]);
    $avg   = $marks->avg();
    $rank  = 0;
    $run   = 0;
    $prev  = null;

    $marks->sort()
        ->reverse()
        ->map(function ($mark, $id) use ($avg, &$rank, &$run, &$prev) {
            $run  = $mark == $prev ? $run + 1 : 0;
            $prev = $mark;
            return [
                'mark' => $mark,
                'rank' => ++$rank - $run,
                'dev'  => $mark - $avg,
                'id'   => $id,
            ];
        })
        ->dump();
}

@burlresearch wow! This is beautiful! Your function is quote nice and can easily be manipulated by yours truly! This is nice! Thanks man