dsyconv.f - Man Page

subroutine dsyconv (uplo, way, n, a, lda, ipiv, e, info)
DSYCONV

DSYCONV  

Purpose:

 DSYCONV convert A given by TRF into L and D and vice-versa.
 Get Non-diag elements of D (returned in workspace) and
 apply or reverse permutation done in TRF.

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*D*U**T;
          = 'L':  Lower triangular, form is A = L*D*L**T.

WAY

          WAY is CHARACTER*1
          = 'C': Convert
          = 'R': Revert

N

          N is INTEGER
          The order of the matrix A.  N >= 0.

A

          A is DOUBLE PRECISION array, dimension (LDA,N)
          The block diagonal matrix D and the multipliers used to
          obtain the factor U or L as computed by DSYTRF.

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 and the block structure of D
          as determined by DSYTRF.

E

          E is DOUBLE PRECISION array, dimension (N)
          E stores the supdiagonal/subdiagonal of the symmetric 1-by-1
          or 2-by-2 block diagonal matrix D in LDLT.

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 113 of file dsyconv.f.