ODE 45 range for the variables
7 views (last 30 days)
Show older comments
Hello.
I used ODE45 to solve a system of differential equations dx/dV, dT/dV where V was assigned as t and x,Y as y(1), y(2) respectively. The code works but the numbers are wrong. I want x to be from 0 to 1 and T to be from 298 to 700. How can I implement these inside the ODE function. Is there a way I don't use tspan as a range of the V variable.
Thank you in advance
2 Comments
Bjorn Gustavsson
on 23 Jun 2020
How are you going to get ode45 to understand what range of V you want to integrate your ODEs over if not by the mechanism used for that? And why wouldn't that be OK.
As for the range of x and T you have to define the boundary-conditions. Since these seems to be first-order ODEs you can define the initial conditions of both (or initial condition of one and end-condition of the other and solve this as a boundary-value problem). Then ode45 will integrate over your period-of-interest. If that takes your solution out of the range you expect, then that's a problem of how you've implemented the ODE or your expectations.
HTH
Answers (1)
Bjorn Gustavsson
on 23 Jun 2020
If you want to start your ode-integration at an [x,T]-point of [0,298] you have to define your y0 like this:
y0=[0 ; 298]; %initial conditions
HTH
0 Comments
See Also
Categories
Find more on Ordinary Differential Equations in Help Center and File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!