dtpcon (3p)

Name

dtpcon - estimate the reciprocal of the condition number of a packed triangular matrix A, in either the 1-norm or the infinity-norm

Synopsis

SUBROUTINE DTPCON(NORM, UPLO, DIAG, N, A, RCOND, WORK, WORK2, INFO)

CHARACTER*1 NORM, UPLO, DIAG
INTEGER N, INFO
INTEGER WORK2(*)
DOUBLE PRECISION RCOND
DOUBLE PRECISION A(*), WORK(*)

SUBROUTINE DTPCON_64(NORM, UPLO, DIAG, N, A, RCOND, WORK, WORK2,
INFO)

CHARACTER*1 NORM, UPLO, DIAG
INTEGER*8 N, INFO
INTEGER*8 WORK2(*)
DOUBLE PRECISION RCOND
DOUBLE PRECISION A(*), WORK(*)




F95 INTERFACE
SUBROUTINE TPCON(NORM, UPLO, DIAG, N, A, RCOND, WORK, WORK2,
INFO)

CHARACTER(LEN=1) :: NORM, UPLO, DIAG
INTEGER :: N, INFO
INTEGER, DIMENSION(:) :: WORK2
REAL(8) :: RCOND
REAL(8), DIMENSION(:) :: A, WORK

SUBROUTINE TPCON_64(NORM, UPLO, DIAG, N, A, RCOND, WORK, WORK2,
INFO)

CHARACTER(LEN=1) :: NORM, UPLO, DIAG
INTEGER(8) :: N, INFO
INTEGER(8), DIMENSION(:) :: WORK2
REAL(8) :: RCOND
REAL(8), DIMENSION(:) :: A, WORK




C INTERFACE
#include <sunperf.h>

void dtpcon(char norm, char uplo, char diag, int n, double  *a,  double
*rcond, int *info);

void dtpcon_64(char norm, char uplo, char diag, long n, double *a, dou-
ble *rcond, long *info);

Description

Oracle Solaris Studio Performance Library                           dtpcon(3P)



NAME
       dtpcon  -  estimate  the reciprocal of the condition number of a packed
       triangular matrix A, in either the 1-norm or the infinity-norm


SYNOPSIS
       SUBROUTINE DTPCON(NORM, UPLO, DIAG, N, A, RCOND, WORK, WORK2, INFO)

       CHARACTER*1 NORM, UPLO, DIAG
       INTEGER N, INFO
       INTEGER WORK2(*)
       DOUBLE PRECISION RCOND
       DOUBLE PRECISION A(*), WORK(*)

       SUBROUTINE DTPCON_64(NORM, UPLO, DIAG, N, A, RCOND, WORK, WORK2,
             INFO)

       CHARACTER*1 NORM, UPLO, DIAG
       INTEGER*8 N, INFO
       INTEGER*8 WORK2(*)
       DOUBLE PRECISION RCOND
       DOUBLE PRECISION A(*), WORK(*)




   F95 INTERFACE
       SUBROUTINE TPCON(NORM, UPLO, DIAG, N, A, RCOND, WORK, WORK2,
              INFO)

       CHARACTER(LEN=1) :: NORM, UPLO, DIAG
       INTEGER :: N, INFO
       INTEGER, DIMENSION(:) :: WORK2
       REAL(8) :: RCOND
       REAL(8), DIMENSION(:) :: A, WORK

       SUBROUTINE TPCON_64(NORM, UPLO, DIAG, N, A, RCOND, WORK, WORK2,
              INFO)

       CHARACTER(LEN=1) :: NORM, UPLO, DIAG
       INTEGER(8) :: N, INFO
       INTEGER(8), DIMENSION(:) :: WORK2
       REAL(8) :: RCOND
       REAL(8), DIMENSION(:) :: A, WORK




   C INTERFACE
       #include <sunperf.h>

       void dtpcon(char norm, char uplo, char diag, int n, double  *a,  double
                 *rcond, int *info);

       void dtpcon_64(char norm, char uplo, char diag, long n, double *a, dou-
                 ble *rcond, long *info);



PURPOSE
       dtpcon estimates the reciprocal of the condition  number  of  a  packed
       triangular matrix A, in either the 1-norm or the infinity-norm.

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


ARGUMENTS
       NORM (input)
                 Specifies whether the 1-norm condition number or  the  infin-
                 ity-norm condition number is required:
                 = '1' or 'O':  1-norm;
                 = 'I':         Infinity-norm.


       UPLO (input)
                 = 'U':  A is upper triangular;
                 = 'L':  A is lower triangular.


       DIAG (input)
                 = 'N':  A is non-unit triangular;
                 = 'U':  A is unit triangular.


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


       A (input) DOUBLE PRECISION array, dimension (N*(N+1)/2)
                 The  upper or lower triangular matrix A, packed columnwise in
                 a linear array.  The j-th column of A is stored in the  array
                 A  as  follows:  if UPLO = 'U', A(i + (j-1)*j/2) = A(i,j) for
                 1<=i<=j; if UPLO = 'L', A(i + (j-1)*(2n-j)/2)  =  A(i,j)  for
                 j<=i<=n.   If  DIAG = 'U', the diagonal elements of A are not
                 referenced and are assumed to be 1.


       RCOND (output)
                 The reciprocal of the condition number of the matrix A,  com-
                 puted as RCOND = 1/(norm(A) * norm(inv(A))).


       WORK (workspace)
                 DOUBLE PRECISION array, dimension(3*N)

       WORK2 (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                        dtpcon(3P)