ctrrfs man page on Cygwin

Man page or keyword search:  
man Server   22533 pages
apropos Keyword Search (all sections)
Output format
Cygwin logo
[printable version]

ctrrfs.f(3)			    LAPACK			   ctrrfs.f(3)

NAME
       ctrrfs.f -

SYNOPSIS
   Functions/Subroutines
       subroutine ctrrfs (UPLO, TRANS, DIAG, N, NRHS, A, LDA, B, LDB, X, LDX,
	   FERR, BERR, WORK, RWORK, INFO)
	   CTRRFS

Function/Subroutine Documentation
   subroutine ctrrfs (characterUPLO, characterTRANS, characterDIAG, integerN,
       integerNRHS, complex, dimension( lda, * )A, integerLDA, complex,
       dimension( ldb, * )B, integerLDB, complex, dimension( ldx, * )X,
       integerLDX, real, dimension( * )FERR, real, dimension( * )BERR,
       complex, dimension( * )WORK, real, dimension( * )RWORK, integerINFO)
       CTRRFS

       Purpose:

	    CTRRFS provides error bounds and backward error estimates for the
	    solution to a system of linear equations with a triangular
	    coefficient matrix.

	    The solution matrix X must be computed by CTRTRS or some other
	    means before entering this routine.	 CTRRFS does not do iterative
	    refinement because doing so cannot improve the backward error.

       Parameters:
	   UPLO

		     UPLO is CHARACTER*1
		     = 'U':  A is upper triangular;
		     = 'L':  A is lower triangular.

	   TRANS

		     TRANS is CHARACTER*1
		     Specifies the form of the system of equations:
		     = 'N':  A * X = B	   (No transpose)
		     = 'T':  A**T * X = B  (Transpose)
		     = 'C':  A**H * X = B  (Conjugate transpose)

	   DIAG

		     DIAG is CHARACTER*1
		     = 'N':  A is non-unit triangular;
		     = 'U':  A is unit triangular.

	   N

		     N is INTEGER
		     The order of the matrix A.	 N >= 0.

	   NRHS

		     NRHS is INTEGER
		     The number of right hand sides, i.e., the number of columns
		     of the matrices B and X.  NRHS >= 0.

	   A

		     A is COMPLEX array, dimension (LDA,N)
		     The triangular matrix A.  If UPLO = 'U', the leading N-by-N
		     upper triangular part of the array A contains the upper
		     triangular matrix, and the strictly lower triangular part of
		     A is not referenced.  If UPLO = 'L', the leading N-by-N lower
		     triangular part of the array A contains the lower triangular
		     matrix, and the strictly upper triangular part of A is not
		     referenced.  If DIAG = 'U', the diagonal elements of A are
		     also not referenced and are assumed to be 1.

	   LDA

		     LDA is INTEGER
		     The leading dimension of the array A.  LDA >= max(1,N).

	   B

		     B is COMPLEX array, dimension (LDB,NRHS)
		     The right hand side matrix B.

	   LDB

		     LDB is INTEGER
		     The leading dimension of the array B.  LDB >= max(1,N).

	   X

		     X is COMPLEX array, dimension (LDX,NRHS)
		     The solution matrix X.

	   LDX

		     LDX is INTEGER
		     The leading dimension of the array X.  LDX >= max(1,N).

	   FERR

		     FERR is REAL array, dimension (NRHS)
		     The estimated forward error bound for each solution vector
		     X(j) (the j-th column of the solution matrix X).
		     If XTRUE is the true solution corresponding to X(j), FERR(j)
		     is an estimated upper bound for the magnitude of the largest
		     element in (X(j) - XTRUE) divided by the magnitude of the
		     largest element in X(j).  The estimate is as reliable as
		     the estimate for RCOND, and is almost always a slight
		     overestimate of the true error.

	   BERR

		     BERR is REAL array, dimension (NRHS)
		     The componentwise relative backward error of each solution
		     vector X(j) (i.e., the smallest relative change in
		     any element of A or B that makes X(j) an exact solution).

	   WORK

		     WORK is COMPLEX array, dimension (2*N)

	   RWORK

		     RWORK is REAL array, dimension (N)

	   INFO

		     INFO is INTEGER
		     = 0:  successful exit
		     < 0:  if INFO = -i, the i-th argument had an illegal value

       Author:
	   Univ. of Tennessee

	   Univ. of California Berkeley

	   Univ. of Colorado Denver

	   NAG Ltd.

       Date:
	   November 2011

       Definition at line 182 of file ctrrfs.f.

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

Version 3.4.2			Sat Nov 16 2013			   ctrrfs.f(3)
[top]

List of man pages available for Cygwin

Copyright (c) for man pages and the logo by the respective OS vendor.

For those who want to learn more, the polarhome community provides shell access and support.

[legal] [privacy] [GNU] [policy] [cookies] [netiquette] [sponsors] [FAQ]
Tweet
Polarhome, production since 1999.
Member of Polarhome portal.
Based on Fawad Halim's script.
....................................................................
Vote for polarhome
Free Shell Accounts :: the biggest list on the net