LAPACK  3.5.0
LAPACK: Linear Algebra PACKage
 All Classes Files Functions Variables Typedefs Macros
csycon_rook.f File Reference

Go to the source code of this file.

Functions/Subroutines

subroutine csycon_rook (UPLO, N, A, LDA, IPIV, ANORM, RCOND, WORK, INFO)
 CSYCON_ROOK More...
 

Function/Subroutine Documentation

subroutine csycon_rook ( character  UPLO,
integer  N,
complex, dimension( lda, * )  A,
integer  LDA,
integer, dimension( * )  IPIV,
real  ANORM,
real  RCOND,
complex, dimension( * )  WORK,
integer  INFO 
)

CSYCON_ROOK

Download CSYCON_ROOK + dependencies [TGZ] [ZIP] [TXT]

Purpose:
 CSYCON_ROOK estimates the reciprocal of the condition number (in the
 1-norm) of a complex symmetric matrix A using the factorization
 A = U*D*U**T or A = L*D*L**T computed by CSYTRF_ROOK.

 An estimate is obtained for norm(inv(A)), and the reciprocal of the
 condition number is computed as RCOND = 1 / (ANORM * norm(inv(A))).
Parameters
[in]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.
[in]N
          N is INTEGER
          The order of the matrix A.  N >= 0.
[in]A
          A is COMPLEX array, dimension (LDA,N)
          The block diagonal matrix D and the multipliers used to
          obtain the factor U or L as computed by CSYTRF_ROOK.
[in]LDA
          LDA is INTEGER
          The leading dimension of the array A.  LDA >= max(1,N).
[in]IPIV
          IPIV is INTEGER array, dimension (N)
          Details of the interchanges and the block structure of D
          as determined by CSYTRF_ROOK.
[in]ANORM
          ANORM is REAL
          The 1-norm of the original matrix A.
[out]RCOND
          RCOND is REAL
          The reciprocal of the condition number of the matrix A,
          computed as RCOND = 1/(ANORM * AINVNM), where AINVNM is an
          estimate of the 1-norm of inv(A) computed in this routine.
[out]WORK
          WORK is COMPLEX array, dimension (2*N)
[out]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.
Date
April 2012
Contributors:

April 2012, Igor Kozachenko, Computer Science Division, University of California, Berkeley

September 2007, Sven Hammarling, Nicholas J. Higham, Craig Lucas, School of Mathematics, University of Manchester

Definition at line 139 of file csycon_rook.f.

Here is the call graph for this function:

Here is the caller graph for this function: