zpttrs(l) [redhat man page]

ZPTTRS(l)								 )								 ZPTTRS(l)

NAME

       ZPTTRS - solve a tridiagonal system of the form A * X = B using the factorization A = U'*D*U or A = L*D*L' computed by ZPTTRF

SYNOPSIS

       SUBROUTINE ZPTTRS( UPLO, N, NRHS, D, E, B, LDB, INFO )

	   CHARACTER	  UPLO

	   INTEGER	  INFO, LDB, N, NRHS

	   DOUBLE	  PRECISION D( * )

	   COMPLEX*16	  B( LDB, * ), E( * )

PURPOSE

       ZPTTRS solves a tridiagonal system of the form A * X = B using the factorization A = U'*D*U or A = L*D*L' computed by ZPTTRF. D is a diago-
       nal matrix specified in the vector D, U (or L) is a unit bidiagonal matrix whose superdiagonal (subdiagonal) is specified in the vector	E,
       and X and B are N by NRHS matrices.

ARGUMENTS

       UPLO    (input) CHARACTER*1
	       Specifies  the form of the factorization and whether the vector E is the superdiagonal of the upper bidiagonal factor U or the sub-
	       diagonal of the lower bidiagonal factor L.  = 'U':  A = U'*D*U, E is the superdiagonal of U
	       = 'L':  A = L*D*L', E is the subdiagonal of L

       N       (input) INTEGER
	       The order of the tridiagonal matrix A.  N >= 0.

       NRHS    (input) INTEGER
	       The number of right hand sides, i.e., the number of columns of the matrix B.  NRHS >= 0.

       D       (input) DOUBLE PRECISION array, dimension (N)
	       The n diagonal elements of the diagonal matrix D from the factorization A = U'*D*U or A = L*D*L'.

       E       (input) COMPLEX*16 array, dimension (N-1)
	       If UPLO = 'U', the (n-1) superdiagonal elements of the unit bidiagonal factor U from the factorization A = U'*D*U.  If UPLO =  'L',
	       the (n-1) subdiagonal elements of the unit bidiagonal factor L from the factorization A = L*D*L'.

       B       (input/output) DOUBLE PRECISION array, dimension (LDB,NRHS)
	       On entry, the right hand side vectors B for the system of linear equations.  On exit, the solution vectors, X.

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

       INFO    (output) INTEGER
	       = 0: successful exit
	       < 0: if INFO = -k, the k-th argument had an illegal value

LAPACK version 3.0						   15 June 2000 							 ZPTTRS(l)

zpttrs.f(3)							      LAPACK							       zpttrs.f(3)

NAME

       zpttrs.f -

SYNOPSIS

   Functions/Subroutines
       subroutine zpttrs (UPLO, N, NRHS, D, E, B, LDB, INFO)
	   ZPTTRS

Function/Subroutine Documentation
   subroutine zpttrs (characterUPLO, integerN, integerNRHS, double precision, dimension( * )D, complex*16, dimension( * )E, complex*16, dimension(
       ldb, * )B, integerLDB, integerINFO)
       ZPTTRS

       Purpose:

	    ZPTTRS solves a tridiagonal system of the form
	       A * X = B
	    using the factorization A = U**H *D* U or A = L*D*L**H computed by ZPTTRF.
	    D is a diagonal matrix specified in the vector D, U (or L) is a unit
	    bidiagonal matrix whose superdiagonal (subdiagonal) is specified in
	    the vector E, and X and B are N by NRHS matrices.

       Parameters:
	   UPLO

		     UPLO is CHARACTER*1
		     Specifies the form of the factorization and whether the
		     vector E is the superdiagonal of the upper bidiagonal factor
		     U or the subdiagonal of the lower bidiagonal factor L.
		     = 'U':  A = U**H *D*U, E is the superdiagonal of U
		     = 'L':  A = L*D*L**H, E is the subdiagonal of L

	   N

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

	   NRHS

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

	   D

		     D is DOUBLE PRECISION array, dimension (N)
		     The n diagonal elements of the diagonal matrix D from the
		     factorization A = U**H *D*U or A = L*D*L**H.

	   E

		     E is COMPLEX*16 array, dimension (N-1)
		     If UPLO = 'U', the (n-1) superdiagonal elements of the unit
		     bidiagonal factor U from the factorization A = U**H*D*U.
		     If UPLO = 'L', the (n-1) subdiagonal elements of the unit
		     bidiagonal factor L from the factorization A = L*D*L**H.

	   B

		     B is DOUBLE PRECISION array, dimension (LDB,NRHS)
		     On entry, the right hand side vectors B for the system of
		     linear equations.
		     On exit, the solution vectors, X.

	   LDB

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

	   INFO

		     INFO is INTEGER
		     = 0: successful exit
		     < 0: if INFO = -k, the k-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 122 of file zpttrs.f.

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

Version 3.4.1							  Sun May 26 2013						       zpttrs.f(3)