Custom Matrix Answer Checker

Answer is a pair of matrices that require a custom answer checker

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Complete Code

Download file: MatrixCustomAnswerChecker.pg

POD for Macro Files

PG problem file

Explanation

DOCUMENT();

loadMacros('PGstandard.pl', 'PGML.pl', 'parserMultiAnswer.pl', 'PGcourse.pl');

$showPartialCorrectAnswers = 0;

Preamble

Since the answer will depend on the two matrices input, we need to use parserMultiAnswer.pl.

Context('Matrix');

$A = Matrix([ [ 1, 1 ], [ 0, 1 ] ]);
$B = Matrix([ [ 1, 0 ], [ 1, 1 ] ]);

$multians = MultiAnswer($A, $B)->with(
    singleResult => 1,
    checker      => sub {
        my ($correct, $student, $answerHash) = @_;
        my @s = @{$student};
        $s0 = Matrix($s[0]);
        $s1 = Matrix($s[1]);
        return $s0 * $s1 != $s1 * $s0;
    }
);

Setup

Construct two matrices $A and $B that do not commute and therefore serve as a correct answer. Use a $multians object with a custom answer checker subroutine. The answer checker uses my ( $correct, $student, $answerHash ) = @_; to grab the inputs (the correct answer, the student answer, and the answer hash table info). Then, put the student’s two answers into an array using my @s = @{$student};. Make sure the student’s first matrix $s[0] is converted to a MathObject matrix using $s0 = Matrix($s[0]); and similarly for the student’s second matrix. The return value, which is boolean, is the truth value of the statement $s0 * $s1 != $s1 * $s0.

BEGIN_PGML
Give an example of two [`2 \times 2`] matrices [`A`] and [`B`] such that
[`AB \ne BA`] .

    [`A =`] [_____]*{$multians}

    [`B =`] [_____]*{$multians}
END_PGML

Statement

Make sure that both answer arrays are called as methods on the $multians object

BEGIN_PGML_SOLUTION
Solution explanation goes here.
END_PGML_SOLUTION

ENDDOCUMENT();

Solution

A solution should be provided here.