MathPHP\LinearAlgebra\Matrix::rowAddScalar PHP Method

    public function rowAddScalar(int $mᵢ, $k) : Matrix
    {
        if ($mᵢ >= $this->m) {
            throw new Exception\MatrixException('Row to add does not exist');
        }
        $n = $this->n;
        $R = $this->A;
        for ($j = 0; $j < $n; $j++) {
            $R[$mᵢ][$j] += $k;
        }
        return MatrixFactory::create($R);
    }