ZPTTRSV(l)						   LAPACK routine (version 2.0) 						ZPTTRSV(l)

NAME

       ZPTTRSV - solve one of the triangular systems  L * X = B, or L**H * X = B,

SYNOPSIS

       SUBROUTINE ZPTTRSV( UPLO, TRANS, N, NRHS, D, E, B, LDB, INFO )

	   CHARACTER	   UPLO, TRANS

	   INTEGER	   INFO, LDB, N, NRHS

	   DOUBLE	   PRECISION D( * )

	   COMPLEX*16	   B( LDB, * ), E( * )

PURPOSE

       ZPTTRSV solves one of the triangular systems
	  L * X = B, or  L**H * X = B,
	  U * X = B, or  U**H * X = B,
       where L or U is the Cholesky factor of a Hermitian positive definite tridiagonal matrix A such that
       A = U**H*D*U or A = L*D*L**H (computed by ZPTTRF).

ARGUMENTS

       UPLO    (input) CHARACTER*1
	       Specifies whether the superdiagonal or the subdiagonal of the tridiagonal matrix A is stored and the form of the factorization:
	       = 'U':  E is the superdiagonal of U, and A = U'*D*U;
	       = 'L':  E is the subdiagonal of L, and A = L*D*L'.  (The two forms are equivalent if A is real.)

       TRANS   (input) CHARACTER
	       Specifies the form of the system of equations:
	       = 'N':  L * X = B     (No transpose)
	       = 'N':  L * X = B     (No transpose)
	       = 'C':  U**H * X = B  (Conjugate transpose)
	       = 'C':  L**H * X = B  (Conjugate transpose)

       N       (input) INTEGER
	       The order of the tridiagonal matrix A.  N >= 0.

       NRHS    (input) INTEGER
	       The number of right hand sides, i.e., the number of columns of the matrix B.  NRHS >= 0.

       D       (input) REAL array, dimension (N)
	       The n diagonal elements of the diagonal matrix D from the factorization computed by ZPTTRF.

       E       (input) COMPLEX array, dimension (N-1)
	       The (n-1) off-diagonal elements of the unit bidiagonal factor U or L from the factorization computed by ZPTTRF (see UPLO).

       B       (input/output) COMPLEX array, dimension (LDB,NRHS)
	       On entry, the right hand side matrix B.	On exit, the solution matrix X.

       LDB     (input) INTEGER
	       The leading dimension of the array B.  LDB >= max(1,N).

       INFO    (output) INTEGER
	       = 0:  successful exit
	       < 0:  if INFO = -i, the i-th argument had an illegal value

modified LAPACK routine 					    12 May 1997 							ZPTTRSV(l)