xodes.m

来自「黄华江所著《实用化工计算机模拟—MATLAB在化学工程中的应用》的所有例子源程序」· M 代码 · 共 27 行

function xODEs
% xODEs.m
% Demonstrate how to use ode45() and ode23() to solve a set of simultaneous ODE equations
%
%   Author: HUANG Huajiang
%   Copyright 2003 UNILAB Research Center, 
%   East China University of Science and Technology, Shanghai, PRC
%   $Revision: 1.0 $  $Date: 2003/02/24 $

clear all
clc

y0 = [0 1];
[x1,y1] = ode45(@f,[0:0.2:1],y0);
[x2,y2] = ode23(@f,[0:0.2:1],y0);

disp('Results by using ode45()：')
disp('    x         y(1)      y(2)')
disp([x1 y1])
disp('Results by using ode23()：')
disp('    x         y(1)      y(2)')
disp([x2 y2])

% ------------------------------------------------------------------
function dydx = f(x,y)      % Define simultaneous ODE equations
dydx = [3*y(1) + 2*y(2); 4*y(1)+y(2)];