Solve a differencial equation with constraints

[Geoffrey Mégardon]

Hi!

I' m trying Sympy this morning and I tried to do this:

equations = [
Eq(a(t).diff(t), (I(t) - gamma*a(t))/theta ),
Eq(a(0), 0),
Eq(I(t), 30) ]

dsolve(equations, a(t))

I was thinking it would try to resolve the first equation with the constraints given by the 2 others equations.
But apparently that doesn't work as I thought.

I also tried with the function:

solve()

But it said it can't resolve the third equation.

Is there a simple way to resolve a set of equations like that?

[Aaron Meurer]

To add initial conditions to dsolve, you need to use the ics
parameter, like dsolve(eq, f(x), ics={f(0):1}). dsolve doesn't
currently integrate with solve to remove the I(t). You'll need to do
that separately, either before or after you run dsolve.

Aaron Meurer

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