system of 1st and 2nd order differential equations ode45
조회 수: 1 (최근 30일)
이전 댓글 표시
I have a system of two 1st order diff eq and one 2nd order diff eq. I want to solve them simultaneously using ode45 and subsequently sum the solutions. I'm having troubles formulating the code for the 2nd order equation. Could you help? The code is:
Fx=@(t,xqxcxm)[ (-xqxcxm(1)+G_q .*(q-q_b)./q_b)./tau_q ;
(-xqxcxm(2) +0.3+3.*tanh(Pa_co2./Pa_co2_b -1.1))./tau_co2 ;
%insert 2nd order diff: xm'' = (-tau2* xm' -xm)/tau1^2 ]
[t, xqxcxm]=ode45(F,[0 100], [0 0 0]);
xq= xqxcxm(:,1);
xc= xqxcxm(:,2);
xm= xqxcxm(:,3);
x=xm+ xc -xq;
댓글 수: 2
Walter Roberson
2017년 10월 18일
It is our policy that we do not remove questions with a relevant Answer, not unless the question was abusive.
답변 (1개)
Josh Meyer
2017년 10월 16일
The documentation explains how to express higher-order equations as first-order equations: Higher-Order ODEs
참고 항목
카테고리
Help Center 및 File Exchange에서 Ordinary Differential Equations에 대해 자세히 알아보기
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!