.TH "SRC/slaqz1.f" 3 "Version 3.12.0" "LAPACK" \" -*- nroff -*- .ad l .nh .SH NAME SRC/slaqz1.f .SH SYNOPSIS .br .PP .SS "Functions/Subroutines" .in +1c .ti -1c .RI "subroutine \fBslaqz1\fP (a, lda, b, ldb, sr1, sr2, si, beta1, beta2, v)" .br .RI "\fBSLAQZ1\fP " .in -1c .SH "Function/Subroutine Documentation" .PP .SS "subroutine slaqz1 (real, dimension( lda, * ), intent(in) a, integer, intent(in) lda, real, dimension( ldb, * ), intent(in) b, integer, intent(in) ldb, real, intent(in) sr1, real, intent(in) sr2, real, intent(in) si, real, intent(in) beta1, real, intent(in) beta2, real, dimension( * ), intent(out) v)" .PP \fBSLAQZ1\fP .PP \fBPurpose:\fP .RS 4 .PP .nf !> !> Given a 3-by-3 matrix pencil (A,B), SLAQZ1 sets v to a !> scalar multiple of the first column of the product !> !> (*) K = (A - (beta2*sr2 - i*si)*B)*B^(-1)*(beta1*A - (sr2 + i*si2)*B)*B^(-1)\&. !> !> It is assumed that either !> !> 1) sr1 = sr2 !> or !> 2) si = 0\&. !> !> This is useful for starting double implicit shift bulges !> in the QZ algorithm\&. !> .fi .PP .RE .PP \fBParameters\fP .RS 4 \fIA\fP .PP .nf !> A is REAL array, dimension (LDA,N) !> The 3-by-3 matrix A in (*)\&. !> .fi .PP .br \fILDA\fP .PP .nf !> LDA is INTEGER !> The leading dimension of A as declared in !> the calling procedure\&. !> .fi .PP .br \fIB\fP .PP .nf !> B is REAL array, dimension (LDB,N) !> The 3-by-3 matrix B in (*)\&. !> .fi .PP .br \fILDB\fP .PP .nf !> LDB is INTEGER !> The leading dimension of B as declared in !> the calling procedure\&. !> .fi .PP .br \fISR1\fP .PP .nf !> SR1 is REAL !> .fi .PP .br \fISR2\fP .PP .nf !> SR2 is REAL !> .fi .PP .br \fISI\fP .PP .nf !> SI is REAL !> .fi .PP .br \fIBETA1\fP .PP .nf !> BETA1 is REAL !> .fi .PP .br \fIBETA2\fP .PP .nf !> BETA2 is REAL !> .fi .PP .br \fIV\fP .PP .nf !> V is REAL array, dimension (N) !> A scalar multiple of the first column of the !> matrix K in (*)\&. !> .fi .PP .RE .PP \fBAuthor\fP .RS 4 Thijs Steel, KU Leuven .RE .PP \fBDate\fP .RS 4 May 2020 .RE .PP .PP Definition at line \fB125\fP of file \fBslaqz1\&.f\fP\&. .SH "Author" .PP Generated automatically by Doxygen for LAPACK from the source code\&.