SRC/dptsv.f(3)             Library Functions Manual             SRC/dptsv.f(3)

NAME
       SRC/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 (integer n, integer nrhs, double precision, dimension( * )
       d, double precision, dimension( * ) e, double precision, dimension(
       ldb, * ) b, integer ldb, integer info)
        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 principal minor of order i
                           is not positive, 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.

       Definition at line 113 of file dptsv.f.

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

LAPACK                          Version 3.12.0                  SRC/dptsv.f(3)