PHPOffice / PhpSpreadsheet

                            $f = -$sn * $e[$j-1];

                            $e[$j-1] = $cs * $e[$j-1];

                        }

                        if ($wantv) {

                            for ($i = 0; $i < $this->n; ++$i) {

                                $t = $cs * $this->V[$i][$j] + $sn * $this->V[$i][$p-1];

                                $this->V[$i][$p-1] = -$sn * $this->V[$i][$j] + $cs * $this->V[$i][$p-1];

                                $this->V[$i][$j] = $t;

                            }

                        }

                    }

                    break;

                // Split at negligible s(k).

                        $this->s[$j] = $t;

                        $f = -$sn * $e[$j];

                        $e[$j] = $cs * $e[$j];

                        if ($wantu) {

                            for ($i = 0; $i < $this->m; ++$i) {

                                $t = $cs * $this->U[$i][$j] + $sn * $this->U[$i][$k-1];

                                $this->U[$i][$k-1] = -$sn * $this->U[$i][$j] + $cs * $this->U[$i][$k-1];

                                $this->U[$i][$j] = $t;

                            }

                        }

                    }

                    break;

                // Perform one qr step.