用来计算保角变换程序

				function M = mtimes(M,c)
				%   Scale the image of a map by a complex constant.
				
				%   Copyright (c) 1998 by Toby Driscoll.
				%   $Id: mtimes.m,v 1.1 1998/06/29 22:34:13 tad Exp $
				
				% May need to swap arguments
				if isa(M,'double') & isa(c,'hplmap')
				  tmp = M;
				  M = c;
				  c = tmp;
				end
				
				M.constant = c*M.constant;
				M.scmap = c*M.scmap;