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

.in +1c
.ti -1c
.RI "double precision function \fBdla_gbrpvgrw\fP (n, kl, ku, ncols, ab, ldab, afb, ldafb)"
.br
.RI "\fBDLA_GBRPVGRW\fP computes the reciprocal pivot growth factor norm(A)/norm(U) for a general banded matrix\&. "
.in -1c
.SH "Function/Subroutine Documentation"
.PP 
.SS "double precision function dla_gbrpvgrw (integer n, integer kl, integer ku, integer ncols, double precision, dimension( ldab, * ) ab, integer ldab, double precision, dimension( ldafb, * ) afb, integer ldafb)"

.PP
\fBDLA_GBRPVGRW\fP computes the reciprocal pivot growth factor norm(A)/norm(U) for a general banded matrix\&.  
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\fBPurpose:\fP
.RS 4

.PP
.nf
 DLA_GBRPVGRW computes the reciprocal pivot growth factor
 norm(A)/norm(U)\&. The 'max absolute element' norm is used\&. If this is
 much less than 1, the stability of the LU factorization of the
 (equilibrated) matrix A could be poor\&. This also means that the
 solution X, estimated condition numbers, and error bounds could be
 unreliable\&.
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.RE
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\fBParameters\fP
.RS 4
\fIN\fP 
.PP
.nf
          N is INTEGER
     The number of linear equations, i\&.e\&., the order of the
     matrix A\&.  N >= 0\&.
.fi
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.br
\fIKL\fP 
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.nf
          KL is INTEGER
     The number of subdiagonals within the band of A\&.  KL >= 0\&.
.fi
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\fIKU\fP 
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          KU is INTEGER
     The number of superdiagonals within the band of A\&.  KU >= 0\&.
.fi
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.br
\fINCOLS\fP 
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          NCOLS is INTEGER
     The number of columns of the matrix A\&.  NCOLS >= 0\&.
.fi
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.br
\fIAB\fP 
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          AB is DOUBLE PRECISION array, dimension (LDAB,N)
     On entry, the matrix A in band storage, 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(N,j+kl)
.fi
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.br
\fILDAB\fP 
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          LDAB is INTEGER
     The leading dimension of the array AB\&.  LDAB >= KL+KU+1\&.
.fi
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\fIAFB\fP 
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          AFB is DOUBLE PRECISION array, dimension (LDAFB,N)
     Details of the LU factorization of the band matrix A, as
     computed by DGBTRF\&.  U is stored as an upper triangular
     band matrix with KL+KU superdiagonals in rows 1 to KL+KU+1,
     and the multipliers used during the factorization are stored
     in rows KL+KU+2 to 2*KL+KU+1\&.
.fi
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.br
\fILDAFB\fP 
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.nf
          LDAFB is INTEGER
     The leading dimension of the array AFB\&.  LDAFB >= 2*KL+KU+1\&.
.fi
.PP
 
.RE
.PP
\fBAuthor\fP
.RS 4
Univ\&. of Tennessee 
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Univ\&. of California Berkeley 
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Univ\&. of Colorado Denver 
.PP
NAG Ltd\&. 
.RE
.PP

.PP
Definition at line \fB115\fP of file \fBdla_gbrpvgrw\&.f\fP\&.
.SH "Author"
.PP 
Generated automatically by Doxygen for LAPACK from the source code\&.