Want to understand how to implement in matlab the following differential equation?

This is the equation I want to write in matlab, so I can have a solution for Q:

Q(t)=(P1(t)-P2)/R +C(dP1/dt) I know P1(t) is a time varing parameter and I know its pattern in time P2 is a costant, R is a costant knows also C. I started implementing it using ode45 to solve differential equations of 1st order and noticed it is not the right manner, because I want to know Q and in the defination of ode45 it finds exactly the first order derivative. Can someone help me by giving adive on how to procced?

Answer 1

[Torsten]

If you know P1 over time, you don't have a differential equation, but simply an algebraic relation to determine Q:

Q = (P1-P2)/R + C*gradient(P1)./gradient(T)

where P1, T are vectors of the same length. T is the time vector corresponding to P1.

[Meri]

Thank you very much, only now I realised that it was so simple. Thank you again for your help