3D_grapher

3D_grapher
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REQUIREMENTS: VMD Version 1.7 or greater
DESCRIPTION:
	draw_surface generates sample points of a function 'g' of two
	variables passed to it. It then draws a smooth surface through
	these points. Only one argument is given to draw_surface, namely
	the function of two variables to plot. Limits of evaluation
	and interval size can be set within the body of the procedure.
	Defaults are -5 to +5 in x and y, with a step size of 0.5. 
	To start you off, a sample function, called 'g' has been provided.
	You may want to just alter this function when plotting your own
	data, to be sure that the syntax is correct.
	
PROCEDURES:
	g - definition of the two-variable function to graph
	draw_surface - calculates points of g and graphs them
EXAMPLE USAGE:
	*To plot the function g, which is a function of two variables 
		draw_surface g
EXAMPLE OUTPUT:
	Image of the default function included
	with the script.
DOWNLOAD FILE:
	3dgraph.tcl
AUTHOR:
	Andrew Dalke (dalke@ks.uiuc.edu)