public function minor(int $mᵢ, int $nⱼ)
{
if (!$this->isSquare()) {
throw new Exception\MatrixException('Matrix is not square; cannot get minor of a non-square matrix');
}
if ($mᵢ >= $this->m || $mᵢ < 0) {
throw new Exception\MatrixException('Row to exclude for minor does not exist');
}
if ($nⱼ >= $this->n || $nⱼ < 0) {
throw new Exception\MatrixException('Column to exclude for minor does not exist');
}
return $this->minorMatrix($mᵢ, $nⱼ)->det();
}