zptsv()

subroutine zptsv	(	integer	n,
		integer	nrhs,
		double precision, dimension( * )	d,
		complex*16, dimension( * )	e,
		complex*16, dimension( ldb, * )	b,
		integer	ldb,
		integer	info )

ZPTSV computes the solution to system of linear equations A * X = B for PT matrices

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Purpose:

!>
!> ZPTSV computes the solution to a complex system of linear equations
!> A*X = B, where A is an N-by-N Hermitian positive definite tridiagonal
!> matrix, and X and B are N-by-NRHS matrices.
!>
!> A is factored as A = L*D*L**H, and the factored form of A is then
!> used to solve the system of equations.
!> 

Parameters

[in]	N	!> N is INTEGER !> The order of the matrix A. N >= 0. !>
[in]	NRHS	!> NRHS is INTEGER !> The number of right hand sides, i.e., the number of columns !> of the matrix B. NRHS >= 0. !>
[in,out]	D	!> D is DOUBLE PRECISION array, dimension (N) !> On entry, the n diagonal elements of the tridiagonal matrix !> A. On exit, the n diagonal elements of the diagonal matrix !> D from the factorization A = L*D*L**H. !>
[in,out]	E	!> E is COMPLEX*16 array, dimension (N-1) !> On entry, the (n-1) subdiagonal elements of the tridiagonal !> matrix A. On exit, the (n-1) subdiagonal elements of the !> unit bidiagonal factor L from the L*D*L**H factorization of !> A. E can also be regarded as the superdiagonal of the unit !> bidiagonal factor U from the U**H*D*U factorization of A. !>
[in,out]	B	!> B is COMPLEX*16 array, dimension (LDB,NRHS) !> On entry, the N-by-NRHS right hand side matrix B. !> On exit, if INFO = 0, the N-by-NRHS solution matrix 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 = -i, the i-th argument had an illegal value !> > 0: if INFO = i, the leading principal minor of order i !> is not positive, and the solution has not been !> computed. The factorization has not been completed !> unless i = N. !>

Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.