pspttrs(3) [debian man page]

PSPTTRS(l)						   LAPACK routine (version 1.5) 						PSPTTRS(l)

NAME

       PSPTTRS - solve a system of linear equations   A(1:N, JA:JA+N-1) * X = B(IB:IB+N-1, 1:NRHS)

SYNOPSIS

       SUBROUTINE PSPTTRS( N, NRHS, D, E, JA, DESCA, B, IB, DESCB, AF, LAF, WORK, LWORK, INFO )

	   INTEGER	   IB, INFO, JA, LAF, LWORK, N, NRHS

	   INTEGER	   DESCA( * ), DESCB( * )

	   REAL 	   AF( * ), B( * ), D( * ), E( * ), WORK( * )

PURPOSE

       PSPTTRS solves a system of linear equations

       where A(1:N, JA:JA+N-1) is the matrix used to produce the factors stored in A(1:N,JA:JA+N-1) and AF by PSPTTRF.
       A(1:N, JA:JA+N-1) is an N-by-N real
       tridiagonal symmetric positive definite distributed
       matrix.

       Routine PSPTTRF MUST be called first.

LAPACK version 1.5						    12 May 1997 							PSPTTRS(l)

CPTSV(l)								 )								  CPTSV(l)

NAME

       CPTSV  - compute the solution to a complex system of linear equations A*X = B, where A is an N-by-N Hermitian positive definite tridiagonal
       matrix, and X and B are N-by-NRHS matrices

SYNOPSIS

       SUBROUTINE CPTSV( N, NRHS, D, E, B, LDB, INFO )

	   INTEGER	 INFO, LDB, N, NRHS

	   REAL 	 D( * )

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

PURPOSE

       CPTSV computes the solution to a complex system of linear equations A*X = B, where A is an N-by-N Hermitian positive  definite  tridiagonal
       matrix,	and X and B are N-by-NRHS matrices.  A is factored as A = L*D*L**H, and the factored form of A is then used to solve the system of
       equations.

ARGUMENTS

       N       (input) INTEGER
	       The order of the 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/output) REAL array, dimension (N)
	       On entry, the n diagonal elements of the tridiagonal matrix A.  On exit, the n diagonal elements of the diagonal matrix D from  the
	       factorization A = L*D*L**H.

       E       (input/output) COMPLEX array, dimension (N-1)
	       On entry, the (n-1) subdiagonal elements of the tridiagonal matrix A.  On exit, the (n-1) subdiagonal elements of the unit bidiago-
	       nal factor L from the L*D*L**H factorization of A.  E can also be regarded as the superdiagonal of the  unit  bidiagonal  factor  U
	       from the U**H*D*U factorization of A.

       B       (input/output) COMPLEX array, dimension (LDB,NRHS)
	       On entry, the N-by-NRHS right hand side matrix B.  On exit, if INFO = 0, the N-by-NRHS solution matrix X.

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

       INFO    (output) INTEGER
	       = 0:  successful exit
	       < 0:  if INFO = -i, the i-th argument had an illegal value
	       >  0:   if INFO = i, the leading minor of order i is not positive definite, and the solution has not been computed.  The factoriza-
	       tion has not been completed unless i = N.

LAPACK version 3.0						   15 June 2000 							  CPTSV(l)