Best coding practices and examples for inference conditional on multidimensional ODE observations?

[xiehw]

And from an old “best ODE practices” thread I dug up, I read the following:

@wds15

Using a stiff sampler for warmup (bdf) and then switch for the sampling phase to a non-stiff solver (RK45) has been shown to be good for some problems. In fact, you can actually switch to the non-stiff solver starting with Phase III of the warmup.

@wds15, how do you switch solvers between the phases? I wasn’t previously aware you could do this.