event.future: process immediate, pending and future events in quantitative...

In byandell/ewing: Ewing's Quantitative Population Ethology

process immediate, pending and future events in quantitative population ethology simulation

Description

Process an event for next individual in a species. Events may be monadic (one individual) or dyadic (involving two individuals).

Usage

event.future(community, species)

Arguments

community	list with initial population data by species
species	name of species with current event

Details

These are the main event processors for Ewing's Quantitative Population Ethology. They all take the same arguments, but handle events in quite different ways. event.future is the generic routine for monadic future events, such as progressing through life stages. event.death handles all pending events of death of individuals.

event.birth handles immediate events of new births. It assumes at present one birth at a time, leading ultimately to a starved state. The future.host data has the gravid adult returning to the fertile state until it depletes its resources. The pending event "starved" then triggers the pending event "death".

event.attack is an example of a dyadic event processor, in this case host-parasite interaction. The parasite locates a host based on life stages and relative position in the simulation space. Ectoparasites kill their hosts, hence realizing a pending death event (to be processed immediately by event.death in the next step). Endoparasites merely incapacitate their hosts.

At present, the search strategies of parasites and health consequences of hosts are crude. However, search is over substrates and depends on the stage of hosts. A crude sex determination strategy is in place, with smaller (younger) hosts more likely to get male parasite eggs.

Simulation counts are stored internally unless the argument 'file' is set to the name of an external file. Following each event, counts are recorded of changes to the number or stage of individuals.

The routine future.events builds the name of the event processor function based on event type, which is established in the future.host or future.parasite data structure. The event.attack uses further information from organism.features about the type of parasite (endo or ecto) in conjunction with the current event (feed or ovip) to determine the nature of attack.

User-supplied event.blah functions can be specified in user-supplied libraries. Note that user code needs to comply with the arguments and values, and needs to process future events for individuals as they progress through life. This is at present an advanced topic, but can be figured out by examining the above routines.

Value

List containing the updated community of species data structures.

Author(s)

Brian S. Yandell

References

See www.stat.wisc.edu/~yandell/ewing.

See Also

future.events, organism.features, future.host

byandell/ewing documentation built on Jan. 3, 2024, 7:27 p.m.