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dptsv.f(3)                          LAPACK                          dptsv.f(3)

NAME
       dptsv.f -

SYNOPSIS
   Functions/Subroutines
       subroutine dptsv (N, NRHS, D, E, B, LDB, INFO)
            DPTSV computes the solution to system of linear equations A * X =
           B for PT matrices

Function/Subroutine Documentation
   subroutine dptsv (integerN, integerNRHS, double precision, dimension( * )D,
       double precision, dimension( * )E, double precision, dimension( ldb, *
       )B, integerLDB, integerINFO)
        DPTSV computes the solution to system of linear equations A * X = B
       for PT matrices

       Purpose:

            DPTSV 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 DOUBLE PRECISION 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 DOUBLE PRECISION 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 DOUBLE PRECISION 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:
           September 2012

       Definition at line 115 of file dptsv.f.

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

Version 3.4.2                   Sat Nov 16 2013                     dptsv.f(3)