Extracting unsolved data from ode45 function

Hi everyone,

I'm trying to create a aircraft model and i have differential equations

i have solved this equations with ode45 and i plotted the states which i want

But i want to plot the unsolved equations too(for example i have u v w from ode45 output but now i want to plot udot vdot and wdot)

How can i do that

Thanks

[J. Alex Lee]

can you just plug your u, v, w into the functions you have defined in the odefun (because they are just of the form du/dt, dv/dt, dw/dt, etc.)?

or are you asking for something else?

[Star Strider]

Use a for loop to provide your ODE function with the solved values and independent variable values in each iteration, and save the outputs. Those will be the derivatives.

[William Rose]

That is yet another excellent answer from @Star Strider.

In case it is not obvious (and it was not obvious to me), he is sggesting that after your line

[t, vecste] = ode45(@(t,vecste)eom(t,vecste,spec,aero,thrust), tspan, stvecinit); 

you do

dydt=zeros(size(vecste));  % allocate array
for i=1:length(dydt)
    [~,dydt(i,:)]=eom(t(i),vecste(i,:),spec,aero,thrust);
end

Good luck!

[Torsten]

Some minor corrections:

dydt = zeros(size(vecste));  % allocate array
dydt = dydt.';
for i=1:numel(t)
    dydt(:,i)=eom(t(i),vecste(i,:),spec,aero,thrust);
end

[William Rose]

Thank you @Torsten

[Muhammed Emin Yavuzaslan]

Thanks to @Torsten @William Rose I appreciate.