How to plot ODE function and I don't get this plot.

5 次查看（过去 30 天）
Myo Gyi
Myo Gyi 2018-9-28
评论： Rena Berman 2018-10-4

请先登录，再回答此问题。

采纳的回答

Torsten
Torsten 2018-9-28
Solve the ODEs using ODE45, e.g., and use "plot3" for the plot.
Best wishes
Torsten.
  2 个评论
Torsten
Torsten 2018-9-28
function main
%Set initial values for r, theta, z
r00 = 10;
theta00 = 0;
z00 = 1.0;
y0 = [r00 theta00 z00];
% Set model parameters
z0 = 0.0;
a = 0.1;
gamma_inf = 1000.0;
nu = 1.0;
% Set integration period
tspan = 0:0.05:10;
% Call integrator
fun = @(t,y)[-a*y(1);gamma_inf/(2*pi*y(1)^2)*(1-exp(-a*y(1)^2/(2*nu)));2*a*(y(3)-z0)];
[T Y] = ode45(fun,tspan,y0)
R = Y(:,1);
THETA = Y(:,2);
Z = Y(:,3);
% Convert polar to cartesian coordinates
[x y] = pol2cart(THETA,R)
% Plot spiral
plot3(x,y,Z)
Myo Gyi
Myo Gyi 2018-9-28
Thank you very much sir..... You are very kind and helpful.

请先登录，再进行评论。

更多回答（0 个）

类别

在 Help Center 和 File Exchange 中查找有关 Ordinary Differential Equations 的更多信息

标签

Community Treasure Hunt

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

Start Hunting!

Translated by