calculate_excretion: Calculate daily excretion (Mid-level - Main function)

In fb4package: 'Fish Bioenergetics 4.0' Model Implementation with High-Performance 'TMB' Backend

Calculate daily excretion (Mid-level - Main function)

Description

Main excretion calculation function called from simulation loop

Usage

calculate_excretion(
  consumption,
  egestion,
  temperature,
  p_value,
  processed_excretion_params
)

Arguments

consumption	Consumption (J/g)
egestion	Egestion (J/g)
temperature	Water temperature (deg C)
p_value	Proportion of maximum consumption (p_value)
processed_excretion_params	List with processed excretion parameters

Value

A non-negative numeric scalar giving the daily excretion rate in J per g fish per day. Returns 0 when consumption is zero. The equation used depends on processed_excretion_params$EXEQ (1 = constant fraction of assimilated energy; 2-3 = temperature- and ration-dependent; 4 = temperature-dependent only).

Examples

# EXEQ 1: constant fraction of assimilated energy
params <- list(EXEQ = 1, UA = 0.1)
calculate_excretion(consumption = 5.0, egestion = 0.8, temperature = 15,
                    p_value = 0.5, processed_excretion_params = params)

fb4package documentation built on May 8, 2026, 1:07 a.m.