这是一些关于MATLAB的小程序

				function [x,y] = eulerpro(fun,x0,xf,y0,h)
				% 功能：用改进的欧拉方法计算一阶常微分方程的初值问题
				% fun: 微分方程的f(x,y)函数句柄或函数名
				% x0: 积分下限
				% xf: 积分上限
				% h: % 积分步长
				%
				%   Author: HUANG Huajiang
				%   Copyright 2003 UNILAB Research Center, 
				%   East China University of Science and Technology, Shanghai, PRC
				%   $Revision: 1.0 $  $Date: 2003/05/21 $
				
				n = fix((xf-x0)/h);
				x(1) = x0;
				y(1) = y0;
				for i = 1:(n-1)
				    x(i+1) = x0 + i*h;
				    y1 = y(i) + h*feval(fun,x(i),y(i));
				    y2 = y(i) + h*feval(fun,x(i+1),y1);
				    y(i+1) = (y1 + y2)/2;
				end