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sptsv(3) [debian man page]

sptsv.f(3)							      LAPACK								sptsv.f(3)

NAME

       sptsv.f -

SYNOPSIS

   Functions/Subroutines
       subroutine sptsv (N, NRHS, D, E, B, LDB, INFO)
	   SPTSV

Function/Subroutine Documentation
   subroutine sptsv (integerN, integerNRHS, real, dimension( * )D, real, dimension( * )E, real, dimension( ldb, * )B, integerLDB, integerINFO)
       SPTSV

       Purpose:

	    SPTSV computes the solution to a real system of linear equations
	    A*X = B, where A is an N-by-N symmetric positive definite tridiagonal
	    matrix, and X and B are N-by-NRHS matrices.

	    A is factored as A = L*D*L**T, and the factored form of A is then
	    used to solve the system of equations.

       Parameters:
	   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 matrix B.  NRHS >= 0.

	   D

		     D is 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**T.

	   E

		     E is REAL 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 bidiagonal factor L from the L*D*L**T factorization of
		     A.  (E can also be regarded as the superdiagonal of the unit
		     bidiagonal factor U from the U**T*D*U factorization of A.)

	   B

		     B is REAL 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

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

	   INFO

		     INFO is 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 factorization has not been completed
			   unless i = N.

       Author:
	   Univ. of Tennessee

	   Univ. of California Berkeley

	   Univ. of Colorado Denver

	   NAG Ltd.

       Date:
	   November 2011

       Definition at line 115 of file sptsv.f.

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

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

Check Out this Related Man Page

SPTSV(l)								 )								  SPTSV(l)

NAME

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

SYNOPSIS

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

	   INTEGER	 INFO, LDB, N, NRHS

	   REAL 	 B( LDB, * ), D( * ), E( * )

PURPOSE

       SPTSV computes the solution to a real system of linear equations A*X = B, where A is an	N-by-N	symmetric  positive  definite  tridiagonal
       matrix,	and X and B are N-by-NRHS matrices.  A is factored as A = L*D*L**T, 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**T.

       E       (input/output) REAL 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**T factorization of A.  (E can also be regarded as the superdiagonal of the unit  bidiagonal  factor  U
	       from the U**T*D*U factorization of A.)

       B       (input/output) REAL 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 							  SPTSV(l)
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