ztbcon ztbtrs ztpcon ztptri ztptrs ztrcon ztrtri ztrtrs

ztptri() void ztptri ( char  uplo, char  diag, int  n, doublecomplex  ap[], int *  info  ) Inverse of a complex triangular matrix in packed form Purpose This routine computes the inverse of a complex upper or lower triangular matrix A stored in packed form. Parameters [in] uplo = 'U': A is upper triangular. = 'L': A is lower triangular. [in] diag = 'N': A is non-unit triangular. = 'U': A is unit triangular. (Diagonal elements of ap[] are not referenced and are assumed to be 1) [in] n Order of the matrix A. (n >= 0) (If n = 0, returns without computation) [in,out] ap[] Array ap[lap] (lap >= n*(n + 1)/2) [in] n x n triangular matrix A in packed symmetric matrix form. Upper or lower part is to be stored in accordance with uplo. [out] The (triangular) inverse of the original matrix, in the same packed form. [out] info = 0: Successful exit = -1: The argument uplo had an illegal value (uplo != 'U' nor 'L') = -2: The argument diag had an illegal value (diag != 'N' nor 'U') = -3: The argument n had an illegal value (n < 0) = i > 0: The i-th diagonal element of A is exactly zero. The triangular matrix is singular and its inverse can not be computed. Reference LAPACK