C+
C NAME:
C	GaussLookup
C PURPOSE:
C	Calculates exp(-x*x-y*y) using lookup table
C CATEGORY:
C	Math
C CALLING SEQUENCE:
	function GaussLookup(X,Y)
C INPUTS:
C	X		real		X-coordinate
C	Y		real		Y-coordinate
C OUTPUTS:
C	F		real		fnc value
C CALLS:
C	FLINT
C SEE ALSO:
C	CosLookup, SinLookup
C MODIFICATION HISTORY:
C	SEP-2003, Paul Hick (UCSD/CASS; pphick@ucsd.edu)
C-
	    real	X
	    real	Y

	parameter	(N  = 1000)
	parameter	(dA = 10.0/N)

	real		F(0:N,0:N)

	integer		ND(2)
	real		PP(2)

	logical		bInit	/.TRUE./
	save		bInit, ND, F

	if (bInit) then		! Set up lookup table

	    ND(1) = N+1
	    ND(2) = N+1

	    A = dA*dA

	    do J=0,N
		J2 = J*J
		do I=0,N
		    I2 = I*I
		    F(I,J) = exp(-A*(I2+J2))
		end do
	    end do

	    bInit = .FALSE.

	end if

	AX = abs(X)/dA
	AY = abs(Y)/dA

	if (AX .le. N .and. AY .le. N) then
	    PP(1) = 1+AX
	    PP(2) = 1+AY
	    GaussLookup = FLINT(2,ND,F,PP,0.0)
	else
	    GaussLookup = 0.0
	end if

	return
	end