Creates and/or destroys agents to get a population number. This function is used as a callback for agent number sliders, and also at the beginning of a model to create the initial agent set.
WARNING: This is an internal function. Its use in user code is not recommended or supported, and its signature can change in future updates without warning. Use one of the suggested functions above instead, if applicable.
model — Helipad, required
The model object. Redundant strictly speaking, but necessary to use the function as a slider callback. See the
prim — str, required
The primitive whose agents to create or destroy
val — int, required
A new population number. If the current population is less than
val, the function creates the difference. If the current population is less than
val, the function destroys agents, maintaining the current proportion between breeds, until the population equals