SUBROUTINE ZPTCON( N, DIAG, OFFD, ANORM, RCOND, WORK, INFO) DOUBLE COMPLEX OFFD(*) INTEGER N, INFO DOUBLE PRECISION ANORM, RCOND DOUBLE PRECISION DIAG(*), WORK(*) SUBROUTINE ZPTCON_64( N, DIAG, OFFD, ANORM, RCOND, WORK, INFO) DOUBLE COMPLEX OFFD(*) INTEGER*8 N, INFO DOUBLE PRECISION ANORM, RCOND DOUBLE PRECISION DIAG(*), WORK(*)
SUBROUTINE PTCON( [N], DIAG, OFFD, ANORM, RCOND, [WORK], [INFO]) COMPLEX(8), DIMENSION(:) :: OFFD INTEGER :: N, INFO REAL(8) :: ANORM, RCOND REAL(8), DIMENSION(:) :: DIAG, WORK SUBROUTINE PTCON_64( [N], DIAG, OFFD, ANORM, RCOND, [WORK], [INFO]) COMPLEX(8), DIMENSION(:) :: OFFD INTEGER(8) :: N, INFO REAL(8) :: ANORM, RCOND REAL(8), DIMENSION(:) :: DIAG, WORK
void zptcon(int n, double *diag, doublecomplex *offd, double anorm, double *rcond, int *info);
void zptcon_64(long n, double *diag, doublecomplex *offd, double anorm, double *rcond, long *info);
Norm(inv(A)) is computed by a direct method, and the reciprocal of the condition number is computed as
RCOND = 1 / (ANORM * norm(inv(A))).