example on solving system of ODEs

Hi, I am absolutely new to diffrax and trying to get the basics of it (great work by the way).

I am a bit confused concerning the syntax for solving systems of ODEs. In the documentation discussing Terms you mention you can solve an Hamiltonian system (coupled ODEs) as a 2-tuple of diffrax.ODETerm.
Consider as a minimal example a simple falling object:
$$\dot{y}(t) = v(t) \quad \dot{v}(t) = -g$$
with g the gravitational constant. What is the correct way of expressing this? I tried the most likely wrong form:

def f1(t,y,args):
return v

def f2(t,v,args):
return -g

term1 = ODETerm(f1)
term2 = ODETerm(f2)
solver = SemiImplicitEuler()
solution = diffeqsolve(terms= (term1, term2), solver= solver, t0=0., t1=1. ,dt0=0.02, y0=(0., 5.) )

And I get: TypeError: unsupported operand type(s) for *: 'DynamicJaxprTracer' and 'function'

That means I am not providing the input in the right form. Could you provide an example on how to implement this correctly ?

Thanks !

Start with the linked Terms documentation and the ODETerm/SemiImplicitEuler entry points; first run the minimal falling-object example from the issue to reproduce the tracer error. Done means the documentation contains a correct, runnable coupled-ODE example and explains the expected state and term structure.