Pre-Workshop Questions or Concerns

[stevencarlislewalker]

Please comment below to raise any questions or concerns that arise before the workshop begins on Thursday March 20, 2022.

[papsti]

In mp_simulator(), it looks like the outputs variable must be specified. However, it would be convenient to have an option to return all available calculated values in the resulting data frame (state variables, flows named with the abs_rate argument, etc.). Is this something you've thought about supporting and decided against (e.g., because the resulting data frames could be really long), or just a feature you haven't implemented (yet?)

[stevencarlislewalker]

You can use mp_simulator(spec, ..., outputs = c(mp_state_vars(spec), mp_flow_vars(spec)))

[stevencarlislewalker]

I don't think that this should be the default but it also needs to be very prominent in the documentation, which is not the case currently.

[papsti]

I don't think that this should be the default but it also needs to be very prominent in the documentation, which is not the case currently.

Agreed, I think it's an undesirable default. Would be good to mention in the mp_simulator() help page but also perhaps in the error message that results when outputs is unspecified (one might reasonably expect that, if outputs is left unspecified, everything will come back).

[stevencarlislewalker]

Ah yes, this error message idea is very good.

[papsti]

in a similar vein to the above, if i'm computing a quantity using a formula, e.g.,

how could i retrieve its value from mp_trajectory()? it is neither a state nor a flow.

EDIT: i realize now i can specify outputs = "lambda" in mp_simulator() 😄

[stevencarlislewalker]

In this case you need to supply it specifically by name, so if you wanted it and all the other variables:

mp_simulator(spec, ..., outputs = c(mp_state_vars(spec), mp_flow_vars(spec), "lambda"))

The key piece of information here is that mp_state_vars and mp_flow_vars are simply returning character vectors ... there is nothing fancy.

[stevencarlislewalker]

oops i missed your edit