dspcon (3p)

Name

dspcon - estimate the reciprocal of the condition number (in the 1-norm) of a real symmetric packed matrix A using the factorization A = U*D*U**T or A = L*D*L**T computed by DSPTRF

Synopsis

SUBROUTINE DSPCON(UPLO, N, A, IPIVOT, ANORM, RCOND, WORK, IWORK2,
INFO)

CHARACTER*1 UPLO
INTEGER N, INFO
INTEGER IPIVOT(*), IWORK2(*)
DOUBLE PRECISION ANORM, RCOND
DOUBLE PRECISION A(*), WORK(*)

SUBROUTINE DSPCON_64(UPLO, N, A, IPIVOT, ANORM, RCOND, WORK, IWORK2,
INFO)

CHARACTER*1 UPLO
INTEGER*8 N, INFO
INTEGER*8 IPIVOT(*), IWORK2(*)
DOUBLE PRECISION ANORM, RCOND
DOUBLE PRECISION A(*), WORK(*)




F95 INTERFACE
SUBROUTINE SPCON(UPLO, N, A, IPIVOT, ANORM, RCOND, WORK, IWORK2,
INFO)

CHARACTER(LEN=1) :: UPLO
INTEGER :: N, INFO
INTEGER, DIMENSION(:) :: IPIVOT, IWORK2
REAL(8) :: ANORM, RCOND
REAL(8), DIMENSION(:) :: A, WORK

SUBROUTINE SPCON_64(UPLO, N, A, IPIVOT, ANORM, RCOND, WORK,
IWORK2, INFO)

CHARACTER(LEN=1) :: UPLO
INTEGER(8) :: N, INFO
INTEGER(8), DIMENSION(:) :: IPIVOT, IWORK2
REAL(8) :: ANORM, RCOND
REAL(8), DIMENSION(:) :: A, WORK




C INTERFACE
#include <sunperf.h>

void  dspcon(char  uplo,  int  n, double *a, int *ipivot, double anorm,
double *rcond, int *info);

void dspcon_64(char uplo, long  n,  double  *a,  long  *ipivot,  double
anorm, double *rcond, long *info);

Description

Oracle Solaris Studio Performance Library                           dspcon(3P)



NAME
       dspcon  -  estimate  the  reciprocal  of  the  condition number (in the
       1-norm) of a real symmetric packed matrix A using the factorization A =
       U*D*U**T or A = L*D*L**T computed by DSPTRF


SYNOPSIS
       SUBROUTINE DSPCON(UPLO, N, A, IPIVOT, ANORM, RCOND, WORK, IWORK2,
             INFO)

       CHARACTER*1 UPLO
       INTEGER N, INFO
       INTEGER IPIVOT(*), IWORK2(*)
       DOUBLE PRECISION ANORM, RCOND
       DOUBLE PRECISION A(*), WORK(*)

       SUBROUTINE DSPCON_64(UPLO, N, A, IPIVOT, ANORM, RCOND, WORK, IWORK2,
             INFO)

       CHARACTER*1 UPLO
       INTEGER*8 N, INFO
       INTEGER*8 IPIVOT(*), IWORK2(*)
       DOUBLE PRECISION ANORM, RCOND
       DOUBLE PRECISION A(*), WORK(*)




   F95 INTERFACE
       SUBROUTINE SPCON(UPLO, N, A, IPIVOT, ANORM, RCOND, WORK, IWORK2,
              INFO)

       CHARACTER(LEN=1) :: UPLO
       INTEGER :: N, INFO
       INTEGER, DIMENSION(:) :: IPIVOT, IWORK2
       REAL(8) :: ANORM, RCOND
       REAL(8), DIMENSION(:) :: A, WORK

       SUBROUTINE SPCON_64(UPLO, N, A, IPIVOT, ANORM, RCOND, WORK,
              IWORK2, INFO)

       CHARACTER(LEN=1) :: UPLO
       INTEGER(8) :: N, INFO
       INTEGER(8), DIMENSION(:) :: IPIVOT, IWORK2
       REAL(8) :: ANORM, RCOND
       REAL(8), DIMENSION(:) :: A, WORK




   C INTERFACE
       #include <sunperf.h>

       void  dspcon(char  uplo,  int  n, double *a, int *ipivot, double anorm,
                 double *rcond, int *info);

       void dspcon_64(char uplo, long  n,  double  *a,  long  *ipivot,  double
                 anorm, double *rcond, long *info);



PURPOSE
       dspcon estimates the reciprocal of the condition number (in the 1-norm)
       of a real symmetric  packed  matrix  A  using  the  factorization  A  =
       U*D*U**T or A = L*D*L**T computed by DSPTRF.

       An  estimate  is  obtained  for norm(inv(A)), and the reciprocal of the
       condition number is computed as RCOND = 1 / (ANORM * norm(inv(A))).


ARGUMENTS
       UPLO (input)
                 Specifies whether the details of the factorization are stored
                 as an upper or lower triangular matrix.  = 'U':  Upper trian-
                 gular, form is A = U*D*U**T;
                 = 'L':  Lower triangular, form is A = L*D*L**T.


       N (input) The order of the matrix A.  N >= 0.


       A (input) Double precision array, dimension (N*(N+1)/2) The block diag-
                 onal matrix D and the multipliers used to obtain the factor U
                 or L as computed by DSPTRF, stored  as  a  packed  triangular
                 matrix.


       IPIVOT (input)
                 Integer  array, dimension (N) Details of the interchanges and
                 the block structure of D as determined by DSPTRF.


       ANORM (input)
                 The 1-norm of the original matrix A.


       RCOND (output)
                 The reciprocal of the condition number of the matrix A,  com-
                 puted as RCOND = 1/(ANORM * AINVNM), where AINVNM is an esti-
                 mate of the 1-norm of inv(A) computed in this routine.


       WORK (workspace)
                 Double precision array, dimension(2*N)

       IWORK2 (workspace)
                 Integer array, dimension(N)


       INFO (output)
                 = 0:  successful exit
                 < 0:  if INFO = -i, the i-th argument had an illegal value




                                  7 Nov 2015                        dspcon(3P)