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dla_gbrpvgrw.f(3)			      LAPACK				dla_gbrpvgrw.f(3)

NAME
       dla_gbrpvgrw.f -

SYNOPSIS
   Functions/Subroutines
       DOUBLE PRECISION function dla_gbrpvgrw (N, KL, KU, NCOLS, AB, LDAB, AFB, LDAFB)
	   DLA_GBRPVGRW computes the reciprocal pivot growth factor norm(A)/norm(U) for a general
	   banded matrix.

Function/Subroutine Documentation
   DOUBLE PRECISION function dla_gbrpvgrw (integerN, integerKL, integerKU, integerNCOLS, double
       precision, dimension( ldab, * )AB, integerLDAB, double precision, dimension( ldafb, *
       )AFB, integerLDAFB)
       DLA_GBRPVGRW computes the reciprocal pivot growth factor norm(A)/norm(U) for a general
       banded matrix.

       Purpose:

	    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.

       Parameters:
	   N

		     N is INTEGER
		The number of linear equations, i.e., the order of the
		matrix A.  N >= 0.

	   KL

		     KL is INTEGER
		The number of subdiagonals within the band of A.  KL >= 0.

	   KU

		     KU is INTEGER
		The number of superdiagonals within the band of A.  KU >= 0.

	   NCOLS

		     NCOLS is INTEGER
		The number of columns of the matrix A.	NCOLS >= 0.

	   AB

		     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)

	   LDAB

		     LDAB is INTEGER
		The leading dimension of the array AB.	LDAB >= KL+KU+1.

	   AFB

		     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.

	   LDAFB

		     LDAFB is INTEGER
		The leading dimension of the array AFB.  LDAFB >= 2*KL+KU+1.

       Author:
	   Univ. of Tennessee

	   Univ. of California Berkeley

	   Univ. of Colorado Denver

	   NAG Ltd.

       Date:
	   September 2012

       Definition at line 117 of file dla_gbrpvgrw.f.

Author
       Generated automatically by Doxygen for LAPACK from the source code.

Version 3.4.2				 Tue Sep 25 2012			dla_gbrpvgrw.f(3)
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