MATLAB Answers

Unexpected output when trying to plot the solution to a system of nonlinear differential equations

조회 수: 1(최근 30일)
Aleem Andrew
Aleem Andrew 3 Apr 2020
댓글: Aleem Andrew 4 Apr 2020
The following Matlab code is meant to plot x(1) vs time and x(2) vs time separately, but only plots x(1) vs time. Despite there being two lines of code to generate each plot, one line is ignored. Does anyone have any suggestions as to how the code can be modified?
t = [0 10]; %time interval ranges from 0 to 10 s
ic = [pi/3; 0; 0; 0]; % initial conditions = [θ θ' x x']
[t,x] = ode45(ode, t, ic);
plot(t,x(:,1), 'o') %the y axis represents
plot( t,x(:,2),'o') %the y axis represents
xlabel('x(m)');
ylabel('θ(rad)');
function dydx = fun(t,x)
%[x(1) x(2) x(3) x(4)] = [angle angular velocity x position x velocity] respectively
L = 0.5; g = 9.81;
dydx = zeros(4,1);
dydx(1) = x(2);
dydx(2) = (4*sin(x(1))*(5*L*cos(x(1))*x(2)^2 + 6*g))/(L*(20*cos(x(1))^2 - 23));
dydx(3) = x(4);
dydx(4) = -(5*sin(x(1))*(23*L*x(2)^2 + 24*g*cos(x(1))))/(6*(20*cos(x(1))^2 - 23));
end

  댓글 수: 0

댓글을 달려면 로그인하십시오.

채택된 답변

Torsten
Torsten 4 Apr 2020
Use
hold on
between the two plot commands.

추가 답변(0개)

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by