README for chullGraham data files
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This directory contains sample input files for
the graham convex hull program (and its variant graham4).

   The input files for the graham program ends in a number
   (the number of points):

	i4, i10, i19, square1000, etc

   The input files for the graham4 program ends in a number 
   and the "w" suffix, indicating the xyzw-format:

	i4w, i10w, i19w, square1000w, square2000w, etc

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DIFFERENCE between graham and graham4 is
just in the format of the input files.

(1) graham input file:
	this is just a sequence of numbers

	   x1 x2 x3 x4 x5 ...

	So the first point is (x1, x2),
	and the next point is (x3, x4), etc.

(2) graham4 input file :
	this is a sequence of quadruples of the form

        	(x1, y1, z1, w1)
        	(x2, y2, z2, w2)
        	(x3, y3, z3, w3)
		...

	where the z-coordinates are 0,
	      the w-coordinates are the homogenizing
	      coordinate (usually set to 1).
	Each quadruple must be in its own line.
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COMMENTS ON THE INPUT FILES:

i4:	This input file (with 4 points)
	will cause an error in Level 1 of graham.cpp

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