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

.in +1c
.ti -1c
.RI "subroutine \fBzgeequb\fP (m, n, a, lda, r, c, rowcnd, colcnd, amax, info)"
.br
.RI "\fBZGEEQUB\fP "
.in -1c
.SH "Function/Subroutine Documentation"
.PP 
.SS "subroutine zgeequb (integer m, integer n, complex*16, dimension( lda, * ) a, integer lda, double precision, dimension( * ) r, double precision, dimension( * ) c, double precision rowcnd, double precision colcnd, double precision amax, integer info)"

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

.PP
.nf
!>
!> ZGEEQUB computes row and column scalings intended to equilibrate an
!> M-by-N matrix A and reduce its condition number\&.  R returns the row
!> scale factors and C the column scale factors, chosen to try to make
!> the largest element in each row and column of the matrix B with
!> elements B(i,j)=R(i)*A(i,j)*C(j) have an absolute value of at most
!> the radix\&.
!>
!> R(i) and C(j) are restricted to be a power of the radix between
!> SMLNUM = smallest safe number and BIGNUM = largest safe number\&.  Use
!> of these scaling factors is not guaranteed to reduce the condition
!> number of A but works well in practice\&.
!>
!> This routine differs from ZGEEQU by restricting the scaling factors
!> to a power of the radix\&.  Barring over- and underflow, scaling by
!> these factors introduces no additional rounding errors\&.  However, the
!> scaled entries' magnitudes are no longer approximately 1 but lie
!> between sqrt(radix) and 1/sqrt(radix)\&.
!> 
.fi
.PP
 
.RE
.PP
\fBParameters\fP
.RS 4
\fIM\fP 
.PP
.nf
!>          M is INTEGER
!>          The number of rows of the matrix A\&.  M >= 0\&.
!> 
.fi
.PP
.br
\fIN\fP 
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.nf
!>          N is INTEGER
!>          The number of columns of the matrix A\&.  N >= 0\&.
!> 
.fi
.PP
.br
\fIA\fP 
.PP
.nf
!>          A is COMPLEX*16 array, dimension (LDA,N)
!>          The M-by-N matrix whose equilibration factors are
!>          to be computed\&.
!> 
.fi
.PP
.br
\fILDA\fP 
.PP
.nf
!>          LDA is INTEGER
!>          The leading dimension of the array A\&.  LDA >= max(1,M)\&.
!> 
.fi
.PP
.br
\fIR\fP 
.PP
.nf
!>          R is DOUBLE PRECISION array, dimension (M)
!>          If INFO = 0 or INFO > M, R contains the row scale factors
!>          for A\&.
!> 
.fi
.PP
.br
\fIC\fP 
.PP
.nf
!>          C is DOUBLE PRECISION array, dimension (N)
!>          If INFO = 0,  C contains the column scale factors for A\&.
!> 
.fi
.PP
.br
\fIROWCND\fP 
.PP
.nf
!>          ROWCND is DOUBLE PRECISION
!>          If INFO = 0 or INFO > M, ROWCND contains the ratio of the
!>          smallest R(i) to the largest R(i)\&.  If ROWCND >= 0\&.1 and
!>          AMAX is neither too large nor too small, it is not worth
!>          scaling by R\&.
!> 
.fi
.PP
.br
\fICOLCND\fP 
.PP
.nf
!>          COLCND is DOUBLE PRECISION
!>          If INFO = 0, COLCND contains the ratio of the smallest
!>          C(i) to the largest C(i)\&.  If COLCND >= 0\&.1, it is not
!>          worth scaling by C\&.
!> 
.fi
.PP
.br
\fIAMAX\fP 
.PP
.nf
!>          AMAX is DOUBLE PRECISION
!>          Absolute value of largest matrix element\&.  If AMAX is very
!>          close to overflow or very close to underflow, the matrix
!>          should be scaled\&.
!> 
.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
!>          > 0:  if INFO = i,  and i is
!>                <= M:  the i-th row of A is exactly zero
!>                >  M:  the (i-M)-th column of A is exactly zero
!> 
.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 \fB145\fP of file \fBzgeequb\&.f\fP\&.
.SH "Author"
.PP 
Generated automatically by Doxygen for LAPACK from the source code\&.