SSPGST(l)		LAPACK routine (version	1.1)		    SSPGST(l)

NAME
  SSPGST - reduce a real symmetric-definite generalized	eigenproblem to	stan-
  dard form, using packed storage

SYNOPSIS

  SUBROUTINE SSPGST( ITYPE, UPLO, N, AP, BP, INFO )

      CHARACTER	     UPLO

      INTEGER	     INFO, ITYPE, N

      REAL	     AP( * ), BP( * )

PURPOSE
  SSPGST reduces a real	symmetric-definite generalized eigenproblem to stan-
  dard form, using packed storage.

  If ITYPE = 1,	the problem is A*x = lambda*B*x,
  and A	is overwritten by inv(U**T)*A*inv(U) or	inv(L)*A*inv(L**T)

  If ITYPE = 2 or 3, the problem is A*B*x = lambda*x or
  B*A*x	= lambda*x, and	A is overwritten by U*A*U**T or	L**T*A*L.

  B must have been previously factorized as U**T*U or L*L**T by	SPPTRF.

ARGUMENTS

  ITYPE	  (input) INTEGER
	  = 1: compute inv(U**T)*A*inv(U) or inv(L)*A*inv(L**T);
	  = 2 or 3: compute U*A*U**T or	L**T*A*L.

  UPLO	  (input) CHARACTER
	  = 'U':  Upper	triangle of A is stored	and B is factored as U**T*U;
	  = 'L':  Lower	triangle of A is stored	and B is factored as L*L**T.

  N	  (input) INTEGER
	  The order of the matrices A and B.  N	>= 0.

  AP	  (input/output) REAL array, dimension (N*(N+1)/2)
	  On entry, the	upper or lower triangle	of the symmetric matrix	A,
	  packed columnwise in a linear	array.	The j-th column	of A is
	  stored in the	array AP as follows: if	UPLO = 'U', AP(i + (j-1)*j/2)
	  = A(i,j) for 1<=i<=j;	if UPLO	= 'L', AP(i + (j-1)*(2n-j)/2) =
	  A(i,j) for j<=i<=n.

	  On exit, if INFO = 0,	the transformed	matrix,	stored in the same
	  format as A.

  BP	  (input) REAL array, dimension	(N*(N+1)/2)
	  The triangular factor	from the Cholesky factorization	of B, stored
	  in the same format as	A, as returned by SPPTRF.

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