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

.in +1c
.ti -1c
.RI "subroutine \fBzgbbrd\fP (vect, m, n, ncc, kl, ku, ab, ldab, d, e, q, ldq, pt, ldpt, c, ldc, work, rwork, info)"
.br
.RI "\fBZGBBRD\fP "
.in -1c
.SH "Function/Subroutine Documentation"
.PP 
.SS "subroutine zgbbrd (character vect, integer m, integer n, integer ncc, integer kl, integer ku, complex*16, dimension( ldab, * ) ab, integer ldab, double precision, dimension( * ) d, double precision, dimension( * ) e, complex*16, dimension( ldq, * ) q, integer ldq, complex*16, dimension( ldpt, * ) pt, integer ldpt, complex*16, dimension( ldc, * ) c, integer ldc, complex*16, dimension( * ) work, double precision, dimension( * ) rwork, integer info)"

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

.PP
.nf
!>
!> ZGBBRD reduces a complex general m-by-n band matrix A to real upper
!> bidiagonal form B by a unitary transformation: Q**H * A * P = B\&.
!>
!> The routine computes B, and optionally forms Q or P**H, or computes
!> Q**H*C for a given matrix C\&.
!> 
.fi
.PP
 
.RE
.PP
\fBParameters\fP
.RS 4
\fIVECT\fP 
.PP
.nf
!>          VECT is CHARACTER*1
!>          Specifies whether or not the matrices Q and P**H are to be
!>          formed\&.
!>          = 'N': do not form Q or P**H;
!>          = 'Q': form Q only;
!>          = 'P': form P**H only;
!>          = 'B': form both\&.
!> 
.fi
.PP
.br
\fIM\fP 
.PP
.nf
!>          M is INTEGER
!>          The number of rows of the matrix A\&.  M >= 0\&.
!> 
.fi
.PP
.br
\fIN\fP 
.PP
.nf
!>          N is INTEGER
!>          The number of columns of the matrix A\&.  N >= 0\&.
!> 
.fi
.PP
.br
\fINCC\fP 
.PP
.nf
!>          NCC is INTEGER
!>          The number of columns of the matrix C\&.  NCC >= 0\&.
!> 
.fi
.PP
.br
\fIKL\fP 
.PP
.nf
!>          KL is INTEGER
!>          The number of subdiagonals of the matrix A\&. KL >= 0\&.
!> 
.fi
.PP
.br
\fIKU\fP 
.PP
.nf
!>          KU is INTEGER
!>          The number of superdiagonals of the matrix A\&. KU >= 0\&.
!> 
.fi
.PP
.br
\fIAB\fP 
.PP
.nf
!>          AB is COMPLEX*16 array, dimension (LDAB,N)
!>          On entry, the m-by-n band matrix A, stored in rows 1 to
!>          KL+KU+1\&. The j-th column of A is stored in the j-th column of
!>          the array AB as follows:
!>          AB(ku+1+i-j,j) = A(i,j) for max(1,j-ku)<=i<=min(m,j+kl)\&.
!>          On exit, A is overwritten by values generated during the
!>          reduction\&.
!> 
.fi
.PP
.br
\fILDAB\fP 
.PP
.nf
!>          LDAB is INTEGER
!>          The leading dimension of the array A\&. LDAB >= KL+KU+1\&.
!> 
.fi
.PP
.br
\fID\fP 
.PP
.nf
!>          D is DOUBLE PRECISION array, dimension (min(M,N))
!>          The diagonal elements of the bidiagonal matrix B\&.
!> 
.fi
.PP
.br
\fIE\fP 
.PP
.nf
!>          E is DOUBLE PRECISION array, dimension (min(M,N)-1)
!>          The superdiagonal elements of the bidiagonal matrix B\&.
!> 
.fi
.PP
.br
\fIQ\fP 
.PP
.nf
!>          Q is COMPLEX*16 array, dimension (LDQ,M)
!>          If VECT = 'Q' or 'B', the m-by-m unitary matrix Q\&.
!>          If VECT = 'N' or 'P', the array Q is not referenced\&.
!> 
.fi
.PP
.br
\fILDQ\fP 
.PP
.nf
!>          LDQ is INTEGER
!>          The leading dimension of the array Q\&.
!>          LDQ >= max(1,M) if VECT = 'Q' or 'B'; LDQ >= 1 otherwise\&.
!> 
.fi
.PP
.br
\fIPT\fP 
.PP
.nf
!>          PT is COMPLEX*16 array, dimension (LDPT,N)
!>          If VECT = 'P' or 'B', the n-by-n unitary matrix P'\&.
!>          If VECT = 'N' or 'Q', the array PT is not referenced\&.
!> 
.fi
.PP
.br
\fILDPT\fP 
.PP
.nf
!>          LDPT is INTEGER
!>          The leading dimension of the array PT\&.
!>          LDPT >= max(1,N) if VECT = 'P' or 'B'; LDPT >= 1 otherwise\&.
!> 
.fi
.PP
.br
\fIC\fP 
.PP
.nf
!>          C is COMPLEX*16 array, dimension (LDC,NCC)
!>          On entry, an m-by-ncc matrix C\&.
!>          On exit, C is overwritten by Q**H*C\&.
!>          C is not referenced if NCC = 0\&.
!> 
.fi
.PP
.br
\fILDC\fP 
.PP
.nf
!>          LDC is INTEGER
!>          The leading dimension of the array C\&.
!>          LDC >= max(1,M) if NCC > 0; LDC >= 1 if NCC = 0\&.
!> 
.fi
.PP
.br
\fIWORK\fP 
.PP
.nf
!>          WORK is COMPLEX*16 array, dimension (max(M,N))
!> 
.fi
.PP
.br
\fIRWORK\fP 
.PP
.nf
!>          RWORK is DOUBLE PRECISION array, dimension (max(M,N))
!> 
.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
Univ\&. of Tennessee 

.PP
Univ\&. of California Berkeley 

.PP
Univ\&. of Colorado Denver 

.PP
NAG Ltd\&. 
.RE
.PP

.PP
Definition at line \fB191\fP of file \fBzgbbrd\&.f\fP\&.
.SH "Author"
.PP 
Generated automatically by Doxygen for LAPACK from the source code\&.