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
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);
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)