dsytrs_aa.f - Man Page

subroutine dsytrs_aa (uplo, n, nrhs, a, lda, ipiv, b, ldb, work, lwork, info)
DSYTRS_AA

DSYTRS_AA  

Purpose:

 DSYTRS_AA solves a system of linear equations A*X = B with a real
 symmetric matrix A using the factorization A = U**T*T*U or
 A = L*T*L**T computed by DSYTRF_AA.

Parameters

UPLO

          UPLO is CHARACTER*1
          Specifies whether the details of the factorization are stored
          as an upper or lower triangular matrix.
          = 'U':  Upper triangular, form is A = U**T*T*U;
          = 'L':  Lower triangular, form is A = L*T*L**T.

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.

A

          A is DOUBLE PRECISION array, dimension (LDA,N)
          Details of factors computed by DSYTRF_AA.

LDA

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

IPIV

          IPIV is INTEGER array, dimension (N)
          Details of the interchanges as computed by DSYTRF_AA.

B

          B is DOUBLE PRECISION array, dimension (LDB,NRHS)
          On entry, the right hand side matrix B.
          On exit, the solution matrix X.

LDB

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

WORK

          WORK is DOUBLE PRECISION array, dimension (MAX(1,LWORK))

LWORK

          LWORK is INTEGER
          The dimension of the array WORK. LWORK >= max(1,3*N-2).

INFO

          INFO is INTEGER
          = 0:  successful exit
          < 0:  if INFO = -i, the i-th argument had an illegal value

Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Definition at line 129 of file dsytrs_aa.f.