cpttrf - compute the L*D*L' factorization of a complex Hermitian positive definite tridiagonal matrix A
SUBROUTINE CPTTRF( N, DIAG, OFFD, INFO) COMPLEX OFFD(*) INTEGER N, INFO REAL DIAG(*)
SUBROUTINE CPTTRF_64( N, DIAG, OFFD, INFO) COMPLEX OFFD(*) INTEGER*8 N, INFO REAL DIAG(*)
SUBROUTINE PTTRF( [N], DIAG, OFFD, [INFO]) COMPLEX, DIMENSION(:) :: OFFD INTEGER :: N, INFO REAL, DIMENSION(:) :: DIAG
SUBROUTINE PTTRF_64( [N], DIAG, OFFD, [INFO]) COMPLEX, DIMENSION(:) :: OFFD INTEGER(8) :: N, INFO REAL, DIMENSION(:) :: DIAG
#include <sunperf.h>
void cpttrf(int n, float *diag, complex *offd, int *info);
void cpttrf_64(long n, float *diag, complex *offd, long *info);
cpttrf computes the L*D*L' factorization of a complex Hermitian positive definite tridiagonal matrix A. The factorization may also be regarded as having the form A = U'*D*U.
= 0: successful exit
< 0: if INFO = -k, the k-th argument had an illegal value
> 0: if INFO = k, the leading minor of order k is not positive definite; if k < N, the factorization could not be completed, while if k = N, the factorization was completed, but DIAG(N) = 0.