How to Get Positions(Ranks) in Laravel

I am building a report card app. My view for pupil's report sheet is like so:

my view SUBJECT CA 1 CA 2 CA AVERAGE EXAM TOTAL PERCENTAGE SUBJECT POSITION Mathematics 80 70 75.0000 56 65.50000000 1st English 70 45 57.5000 100 78.75000000 3rd
Biology 89 23 56.0000 90 73.00000000 4th

In my results table in DB, I have columns: student_id, studentClass, CA1, CA2, Examination and other essentials. I do not a total percentage, CA Average nor Overall Percentage column. The Overall Percentage is gotten by Total Percentage/Number of Subjects (in the above example : 72.416666666667). The CA Average and Total Percentage are calculated on the fly using query builder as you will find in my controller below.

What I need is to calculate 1. Positions in class e.g Elementary 1A. Each pupil is assigned a position based on Overall Percentage. like 1st, 2nd, 3rd etc. And of course if there's a tie, the next position is skipped. 2. Positions across arms e.g Eementary can have Elementary 1A, 1B, 1C etc. I need to assign positions to pupils by overall percentage in comparison to all pupils in Elementary(1A, 1B, 1C etc.). 3. Subject Positions: This is calculated using Total Percentage scored by a pupil in each subject, in comparison with other pupils in same class, e.g Elementary 1A. It's the last column in my view above. I could find a fix for it either.

I have searched for solutions.What I have seen so far were solutions where the Position(rank) is calculated using a column on the DB table. In my case I do not have such column, as I used QB to calculate on the fly. I did try to implement that method by calculating at least CA Average and Total Percentage during insert but got 'unsupported operand' error.

My Controller:

public function studentresultsheet(Request $request){

        $stclass = $request->get('stclass');
        $myclass = Stclass::find($request->get('stclass'))->name;
        $studentId = $request->get('studentId');
        $studentname = Student::find($request->get('studentId'))->surname;

        $session= $request->get('sessionnow');
        $term = $request->get('term');

        $myids = Stclass::find($stclass)->students;

        // $dodo = DB::table('results')
        //           -> where('studentClass', $stclass)->where('session', $session)->where('term', $term)
        //           ->selectRaw('results.studentId')->distinct()->get();







         $resultpercent = DB::table('results')
                  -> where('studentClass', $stclass)->where('session', $session)->where('term', $term)->where('studentId', $studentId)
                  ->selectRaw("SUM((results.exam + (results.test1 + results.test2)/2)/2)/(COUNT(results.subject)) as overallpercent")->get();

                   $dodo = DB::table('results')
                  -> where('studentClass', $stclass)->where('session', $session)->where('term', $term)
                  ->selectRaw('results.studentId')->get();



         $results = DB::table('results')
                    ->where('studentClass', $stclass)->where('session', $session)->where('term', $term)->where('studentId', $studentId)
                    ->selectRaw('results.*, (results.test1 + results.test2)/2 as cav, (results.exam + (results.test1 + results.test2)/2)/2 as totalmark')->get();

      return view('admin.results.studentresultsheet', compact('results', 'myclass', 'studentname','resultpercent', 'countsubjects'));

}

Thanks.

via Chebli Mohamed