Describe an epoch within a multistage_parameters object
multistage_epoch(start, pars = NULL, transform_state = NULL)The start time, in units of time in your data set.
These must correspond to time points with data. The model will
complete the step to this time point, then change parameters,
then continue (so start represents the time point we move from
with these parameters)
Optional parameter object, replacing the model
parameters at this point. If NULL then the model parameters
are not changed, and it is assumed that you will be changing
model state via transform_state.
Optional parameter transformation function.
This could be used in two cases (1) arbitrary change to the
model state (e.g., a one-off movement of state within particles
at a given time point that would be otherwise awkward to code
directly in your model), or (2) where you have provided pars
and these imply a different model state size. In this case you
must provide transform_state to fill in new model state,
move things around, or delete model state depending on how the
state has changed. This function will be passed three
arguments: (1) the current model state, (2) the result of the
$info() method from the model used to this point, (3) the
result of the $info() method for the new model that was
created with pars which will be run from this point. Future
versions of this interface may allow passing the parameters in
too.