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