.TH "SRC/slaqz4.f" 3 "Version 3.12.0" "LAPACK" \" -*- nroff -*-
.ad l
.nh
.SH NAME
SRC/slaqz4.f
.SH SYNOPSIS
.br
.PP
.SS "Functions/Subroutines"

.in +1c
.ti -1c
.RI "subroutine \fBslaqz4\fP (ilschur, ilq, ilz, n, ilo, ihi, nshifts, nblock_desired, sr, si, ss, a, lda, b, ldb, q, ldq, z, ldz, qc, ldqc, zc, ldzc, work, lwork, info)"
.br
.RI "\fBSLAQZ4\fP "
.in -1c
.SH "Function/Subroutine Documentation"
.PP 
.SS "subroutine slaqz4 (logical, intent(in) ilschur, logical, intent(in) ilq, logical, intent(in) ilz, integer, intent(in) n, integer, intent(in) ilo, integer, intent(in) ihi, integer, intent(in) nshifts, integer, intent(in) nblock_desired, real, dimension( * ), intent(inout) sr, real, dimension( * ), intent(inout) si, real, dimension( * ), intent(inout) ss, real, dimension( lda, * ), intent(inout) a, integer, intent(in) lda, real, dimension( ldb, * ), intent(inout) b, integer, intent(in) ldb, real, dimension( ldq, * ), intent(inout) q, integer, intent(in) ldq, real, dimension( ldz, * ), intent(inout) z, integer, intent(in) ldz, real, dimension( ldqc, * ), intent(inout) qc, integer, intent(in) ldqc, real, dimension( ldzc, * ), intent(inout) zc, integer, intent(in) ldzc, real, dimension( * ), intent(inout) work, integer, intent(in) lwork, integer, intent(out) info)"

.PP
\fBSLAQZ4\fP  
.PP
\fBPurpose:\fP
.RS 4

.PP
.nf
 SLAQZ4 Executes a single multishift QZ sweep
.fi
.PP
 
.RE
.PP
\fBParameters\fP
.RS 4
\fIILSCHUR\fP 
.PP
.nf
          ILSCHUR is LOGICAL
              Determines whether or not to update the full Schur form
.fi
.PP
.br
\fIILQ\fP 
.PP
.nf
          ILQ is LOGICAL
              Determines whether or not to update the matrix Q
.fi
.PP
.br
\fIILZ\fP 
.PP
.nf
          ILZ is LOGICAL
              Determines whether or not to update the matrix Z
.fi
.PP
.br
\fIN\fP 
.PP
.nf
          N is INTEGER
          The order of the matrices A, B, Q, and Z\&.  N >= 0\&.
.fi
.PP
.br
\fIILO\fP 
.PP
.nf
          ILO is INTEGER
.fi
.PP
.br
\fIIHI\fP 
.PP
.nf
          IHI is INTEGER
.fi
.PP
.br
\fINSHIFTS\fP 
.PP
.nf
          NSHIFTS is INTEGER
          The desired number of shifts to use
.fi
.PP
.br
\fINBLOCK_DESIRED\fP 
.PP
.nf
          NBLOCK_DESIRED is INTEGER
          The desired size of the computational windows
.fi
.PP
.br
\fISR\fP 
.PP
.nf
          SR is REAL array\&. SR contains
          the real parts of the shifts to use\&.
.fi
.PP
.br
\fISI\fP 
.PP
.nf
          SI is REAL array\&. SI contains
          the imaginary parts of the shifts to use\&.
.fi
.PP
.br
\fISS\fP 
.PP
.nf
          SS is REAL array\&. SS contains
          the scale of the shifts to use\&.
.fi
.PP
.br
\fIA\fP 
.PP
.nf
          A is REAL array, dimension (LDA, N)
.fi
.PP
.br
\fILDA\fP 
.PP
.nf
          LDA is INTEGER
          The leading dimension of the array A\&.  LDA >= max( 1, N )\&.
.fi
.PP
.br
\fIB\fP 
.PP
.nf
          B is REAL array, dimension (LDB, N)
.fi
.PP
.br
\fILDB\fP 
.PP
.nf
          LDB is INTEGER
          The leading dimension of the array B\&.  LDB >= max( 1, N )\&.
.fi
.PP
.br
\fIQ\fP 
.PP
.nf
          Q is REAL array, dimension (LDQ, N)
.fi
.PP
.br
\fILDQ\fP 
.PP
.nf
          LDQ is INTEGER
.fi
.PP
.br
\fIZ\fP 
.PP
.nf
          Z is REAL array, dimension (LDZ, N)
.fi
.PP
.br
\fILDZ\fP 
.PP
.nf
          LDZ is INTEGER
.fi
.PP
.br
\fIQC\fP 
.PP
.nf
          QC is REAL array, dimension (LDQC, NBLOCK_DESIRED)
.fi
.PP
.br
\fILDQC\fP 
.PP
.nf
          LDQC is INTEGER
.fi
.PP
.br
\fIZC\fP 
.PP
.nf
          ZC is REAL array, dimension (LDZC, NBLOCK_DESIRED)
.fi
.PP
.br
\fILDZC\fP 
.PP
.nf
          LDZ is INTEGER
.fi
.PP
.br
\fIWORK\fP 
.PP
.nf
          WORK is REAL array, dimension (MAX(1,LWORK))
          On exit, if INFO >= 0, WORK(1) returns the optimal LWORK\&.
.fi
.PP
.br
\fILWORK\fP 
.PP
.nf
          LWORK is INTEGER
          The dimension of the array WORK\&.  LWORK >= max(1,N)\&.

          If LWORK = -1, then a workspace query is assumed; the routine
          only calculates the optimal size of the WORK array, returns
          this value as the first entry of the WORK array, and no error
          message related to LWORK is issued by XERBLA\&.
.fi
.PP
.br
\fIINFO\fP 
.PP
.nf
          INFO is INTEGER
          = 0: successful exit
          < 0: if INFO = -i, the i-th argument had an illegal value
.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 \fB210\fP of file \fBslaqz4\&.f\fP\&.
.SH "Author"
.PP 
Generated automatically by Doxygen for LAPACK from the source code\&.