subroutine	IRPL_GREATXSMALL

 Purpose       intersections between a great circle and a small circle

 File		irpl_greatxsmall.shl

 Class		IRAS, Math

 Author        850712 Uwe Peppel

 Use  subroutine IRPL_GREATXSMALL(
	polegc, 	I	doubleprecision(3)
	theta, 		I	real
	pint, 		O	real(3,2)
	nrint )         O	integer
 	polegc  	coordinates of one pole of the great circle
       theta   	polar angle of the small circle (in rad)
       pint    	intersection points
       nrint    	number of intersection points found

 Description	The input parameters have to be given in a rectangular
            coordinate system with the z-axis pointing to the
            center of the small circle. The great circle has to
            be specified by the coordinates of one of its
            poles, the small circle by its polar angle.
            If intersection points are found, they are given by the
            array PINT. nrint can be 0, 1, or 2. nrint =1 means that
            the two circles have one common point. For the trivial case
            of THETA = 90 and POLEGC = (0,0,1) where the two circles
            are identical, nrint is given the value -1.

 Update	900911	DK, all real variables to doubleprecision