zgttrs()

subroutine zgttrs	(	character	TRANS,
		integer	N,
		integer	NRHS,
		complex*16, dimension( * )	DL,
		complex*16, dimension( * )	D,
		complex*16, dimension( * )	DU,
		complex*16, dimension( * )	DU2,
		integer, dimension( * )	IPIV,
		complex*16, dimension( ldb, * )	B,
		integer	LDB,
		integer	INFO
	)

ZGTTRS

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Purpose:

 ZGTTRS solves one of the systems of equations
    A * X = B,  A**T * X = B,  or  A**H * X = B,
 with a tridiagonal matrix A using the LU factorization computed
 by ZGTTRF.

Parameters

[in]	TRANS	TRANS is CHARACTER*1 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]	N	N is INTEGER The order of the matrix A.
[in]	NRHS	NRHS is INTEGER The number of right hand sides, i.e., the number of columns of the matrix B. NRHS >= 0.
[in]	DL	DL is COMPLEX*16 array, dimension (N-1) The (n-1) multipliers that define the matrix L from the LU factorization of A.
[in]	D	D is COMPLEX*16 array, dimension (N) The n diagonal elements of the upper triangular matrix U from the LU factorization of A.
[in]	DU	DU is COMPLEX*16 array, dimension (N-1) The (n-1) elements of the first super-diagonal of U.
[in]	DU2	DU2 is COMPLEX*16 array, dimension (N-2) The (n-2) elements of the second super-diagonal of U.
[in]	IPIV	IPIV is INTEGER array, dimension (N) The pivot indices; for 1 <= i <= n, row i of the matrix was interchanged with row IPIV(i). IPIV(i) will always be either i or i+1; IPIV(i) = i indicates a row interchange was not required.
[in,out]	B	B is COMPLEX*16 array, dimension (LDB,NRHS) On entry, the matrix of right hand side vectors B. On exit, B is overwritten by the solution vectors X.
[in]	LDB	LDB is INTEGER The leading dimension of the array B. LDB >= max(1,N).
[out]	INFO	INFO is INTEGER = 0: successful exit < 0: if INFO = -k, the k-th argument had an illegal value

Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.