◆ ztptrs()

Solution to system of linear equations AX = B, A^TX = B or A^HX = B for a complex triangular matrix in packed form

Purpose: This routine solves a triangular system of the form
A * X = B, A^T * X = B or A^H * X = B

where A is a triangular matrix of order n stored in packed form, and B is an n x nrhs matrix. A check is made to verify that A is nonsingular.

Parameters

[in]	uplo	= 'U': A is upper triangular. = 'L': A is lower triangular.
[in]	trans	Specifies the form of the system of equations: = 'N': A * X = B. (no transpose) = 'T': A^T * X = B. (transpose) = 'C': A^H * X = B. (conjugate transpose)
[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]	nrhs	Number of right hand sides, i.e., number of columns of the matrix B. (nrhs >= 0) (if nrhs = 0, returns without computation)
[in]	ap[]	Array ap[lap] (lap >= n(n + 1)/2) n x n triangular matrix A in packed symmetric matrix form. Upper or lower part is to be stored in accordance with uplo.
[in]	ldb	Leading dimension of the two dimensional array b[][]. (ldb >= max(1, n))
[in,out]	b[][]	Array b[lb][ldb] (lb >= nrhs) [in] Right hand side matrix B. [out] If info = 0, the solution matrix X.
[out]	info	= 0: Successful exit = -1: The argument norm had an illegal value (norm != '1', 'O' nor 'I') = -2: The argument uplo had an illegal value (uplo != 'U' nor 'L') = -3: The argument diag had an illegal value (diag != 'N' nor 'U') = -4: The argument n had an illegal value (n < 0) = -5: The argument nrhs had an illegal value (nrhs < 0) = -7: The argument ldb had an illegal value (ldb < max(1, n)) = i > 0: The i-th diagonal element of A is zero, indicating that the matrix is singular and the solutions X have not been computed.