Unix/Linux Go Back    


CentOS 7.0 - man page for sla_gbrpvgrw (centos section 3)

Linux & Unix Commands - Search Man Pages
Man Page or Keyword Search:   man
Select Man Page Set:       apropos Keyword Search (sections above)


sla_gbrpvgrw.f(3)			      LAPACK				sla_gbrpvgrw.f(3)

NAME
       sla_gbrpvgrw.f -

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

Function/Subroutine Documentation
   REAL function sla_gbrpvgrw (integerN, integerKL, integerKU, integerNCOLS, real, dimension(
       ldab, * )AB, integerLDAB, real, dimension( ldafb, * )AFB, integerLDAFB)
       SLA_GBRPVGRW computes the reciprocal pivot growth factor norm(A)/norm(U) for a general
       banded matrix.

       Purpose:

	    SLA_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 REAL 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 REAL array, dimension (LDAFB,N)
		Details of the LU factorization of the band matrix A, as
		computed by SGBTRF.  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 sla_gbrpvgrw.f.

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

Version 3.4.2				 Tue Sep 25 2012			sla_gbrpvgrw.f(3)
Unix & Linux Commands & Man Pages : ©2000 - 2018 Unix and Linux Forums


All times are GMT -4. The time now is 12:38 AM.