src/Maths/Algebra/Matrix.php
public function getLine($index = null)
    {
        if (is_null($index)) {
            $index = $this->keyX();
        }
        try {
            $this->seekX($index);
        } catch (OutOfRangeException $e) {
            throw $e;
        }
        return $this->currentX();
    }
public function getLine($index = null)
    {
        if (is_null($index)) {
            $index = $this->keyX();
        }
        try {
            $this->seekX($index);
        } catch (OutOfRangeException $e) {
            throw $e;
        }
        return $this->currentX();
    }
Get a line value (specifying an optional index)

@param   int    $index
@return  array|null
@throws  OutOfRangeException