Save intermediate computations so that they can be used as factors in rate expressions and returned as part of the simulation history. The definition of a factor is given here: https://canmod.net/misc/flex_specs#v0.1.0.
add_factr(model, factr_nm, formula)flexmodel object
name of the new intermediate factor
formula (or string) that follows
this spec, https://canmod.net/misc/flex_specs#v0.1.0,
or 1-by-1 struc-class object describing the
intermediate factor. See avail_for_factr for
a function that will return the names of all variables that are available
for use in these formulas and struc-class objects.
updated flexmodel object
See vec_factr to add more than
one intermediate factor at the same time.
Other flexmodel_definition_functions:
add_linearized_outflow(),
add_parallel_accumulators(),
add_rate(),
add_state_mappings(),
add_state_param_sum(),
initial_population(),
mat_rate(),
rep_rate(),
update_disease_free_state(),
update_linearized_params(),
update_tmb_indices(),
vec_rate()