NAME:
	inslit
PURPOSE: (one line)
	Compute flux passing through a slit assuming a gaussian image.
CATEGORY
       Spectroscopy
DESCRIPTION:

CALLING SEQUENCE:
	inslit,width,height,fwhm,offset
INPUTS:
	width  - Width of slit.
	height - Height of slit.
	fwhm   - Full-width at half-maximum of the gaussian image.
	offset - Offset of the image from center of the slit.

	Note: the units are arbitrary but they must be the same within
	all of the input quantities.  The object is also assumed to
	be perfectly centered in the vertical direction.
OUTPUTS:
	Returned is the fraction of the total gaussian included in the slit.
REVISION HISTORY:
	Written 1991 Mar., Marc W. Buie, Lowell Observatory
COMMENTS: