SGTTRS(l)		LAPACK routine (version	1.1)		    SGTTRS(l)

NAME
  SGTTRS - solve one of	the systems of equations  A*X =	B or A'*X = B,

SYNOPSIS

  SUBROUTINE SGTTRS( TRANS, N, NRHS, DL, D, DU,	DU2, IPIV, B, LDB, INFO	)

      CHARACTER	     TRANS

      INTEGER	     INFO, LDB,	N, NRHS

      INTEGER	     IPIV( * )

      REAL	     B(	LDB, * ), D( * ), DL( *	), DU( * ), DU2( * )

PURPOSE
  SGTTRS solves	one of the systems of equations
     A*X = B  or  A'*X = B, with a tridiagonal matrix A	using the LU factori-
  zation computed by SGTTRF.

ARGUMENTS

  TRANS	  (input) CHARACTER
	  Specifies the	form of	the system of equations:
	  = 'N':  A * X	= B  (No transpose)
	  = 'T':  A'* X	= B  (Transpose)
	  = 'C':  A'* X	= B  (Conjugate	transpose = Transpose)

  N	  (input) INTEGER
	  The order of the matrix A.

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

  DL	  (input) REAL array, dimension	(N-1)
	  The (n-1) multipliers	that define the	matrix L from the LU factori-
	  zation of A.

  D	  (input) REAL array, dimension	(N)
	  The n	diagonal elements of the upper triangular matrix U from	the
	  LU factorization of A.

  DU	  (input) REAL array, dimension	(N-1)
	  The (n-1) elements of	the first superdiagonal	of U.

  DU2	  (input) REAL array, dimension	(N-2)
	  The (n-2) elements of	the second superdiagonal of U.

  IPIV	  (input) INTEGER array, dimension (N)
	  The pivot indices; for 1 <= i	<= n, row i of the matrix was inter-
	  changed with row IPIV(i).  IPIV(i) will always be either i or	i+1;
	  IPIV(i) = i indicates	a row interchange was not required.

  B	  (input/output) REAL array, dimension (LDB,NRHS)
	  On entry, the	right hand side	matrix B.  On exit, B is overwritten
	  by 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