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dposv.f(3)                          LAPACK                          dposv.f(3)

NAME
       dposv.f -

SYNOPSIS
   Functions/Subroutines
       subroutine dposv (UPLO, N, NRHS, A, LDA, B, LDB, INFO)
            DPOSV computes the solution to system of linear equations A * X =
           B for PO matrices

Function/Subroutine Documentation
   subroutine dposv (characterUPLO, integerN, integerNRHS, double precision,
       dimension( lda, * )A, integerLDA, double precision, dimension( ldb, *
       )B, integerLDB, integerINFO)
        DPOSV computes the solution to system of linear equations A * X = B
       for PO matrices

       Purpose:

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

            The Cholesky decomposition is used to factor A as
               A = U**T* U,  if UPLO = 'U', or
               A = L * L**T,  if UPLO = 'L',
            where U is an upper triangular matrix and L is a lower triangular
            matrix.  The factored form of A is then used to solve the system of
            equations A * X = B.

       Parameters:
           UPLO

                     UPLO is CHARACTER*1
                     = 'U':  Upper triangle of A is stored;
                     = 'L':  Lower triangle of A is stored.

           N

                     N is INTEGER
                     The number of linear equations, i.e., 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.

           A

                     A is DOUBLE PRECISION array, dimension (LDA,N)
                     On entry, the symmetric matrix A.  If UPLO = 'U', the leading
                     N-by-N upper triangular part of A contains the upper
                     triangular part of the matrix A, and the strictly lower
                     triangular part of A is not referenced.  If UPLO = 'L', the
                     leading N-by-N lower triangular part of A contains the lower
                     triangular part of the matrix A, and the strictly upper
                     triangular part of A is not referenced.

                     On exit, if INFO = 0, the factor U or L from the Cholesky
                     factorization A = U**T*U or A = L*L**T.

           LDA

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

           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 of A is not
                           positive definite, so the factorization could not be
                           completed, and the solution has not been computed.

       Author:
           Univ. of Tennessee

           Univ. of California Berkeley

           Univ. of Colorado Denver

           NAG Ltd.

       Date:
           November 2011

       Definition at line 131 of file dposv.f.

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

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