Fauna::FatmassEnergyBudget Class Reference

A herbivore’s energy budget with fat reserves. More...

#include <fatmass_energy_budget.h>

Public Member Functions
	FatmassEnergyBudget (const double initial_fatmass, const double maximum_fatmass, const double anabolism_coefficient, const double catabolism_coefficient)
	Constructor. More...
void	add_energy_needs (const double energy)
	Increase energy needs. More...
void	catabolize_fat ()
	Burn fat reserves and reduce unmet energy needs. More...
void	force_body_condition (const double body_condition)
	Set the proportional fat reserves. More...
double	get_energy_needs () const
	Current energy needs [MJ/ind]. More...
double	get_fatmass () const
	Current fat mass [kg/ind]. More...
double	get_max_anabolism_per_day () const
	Get the maximum energy [MJ/ind/day] that could be anabolized in a day. More...
double	get_max_fatmass () const
	Maximum fat mass [kg/ind]. More...
void	merge (const FatmassEnergyBudget &other, const double this_weight, const double other_weight)
	Merge this object with another one by building weighted averages. More...
void	metabolize_energy (double energy)
	Update budget and fat mass by receiving energy (through feeding) More...
void	set_max_fatmass (const double max_fatmass, const double max_gain)
	Set the maximum allowed fat mass [kg/ind] and fat gain [kg/ind/day]. More...

Private Attributes
double	anabolism_coefficient
double	catabolism_coefficient
double	energy_needs = 0.0
double	fatmass
double	max_fatmass
double	max_fatmass_gain = 0.0

Detailed Description

A herbivore’s energy budget with fat reserves.

Terminology:

• Anabolism = build up fat mass
• Catabolism = burn fat mass
• Metabolism = burn food energy directly and use surplus for anabolism

Constructor & Destructor Documentation

FatmassEnergyBudget()

FatmassEnergyBudget::FatmassEnergyBudget	(	const double	initial_fatmass,
		const double	maximum_fatmass,
		const double	anabolism_coefficient,
		const double	catabolism_coefficient
	)

Constructor.

Parameters

initial_fatmass	Initial fat mass [kg/ind]
maximum_fatmass	Maximum fat mass [kg/ind]
anabolism_coefficient	Conversion factor from net forage energy to fat mass [MJ/kg]. See Section Energy Content of Forage for how this value can be derived.
catabolism_coefficient	Conversion factor from fat mass to net energy [MJ/kg]. This is basically gross (combustion) energy of fat mass multiplied by conversion efficiency.

Exceptions

std::invalid_argument	If one parameter is <=0.0
std::logic_error	initial_fatmass > maximum_fatmass

Member Function Documentation

add_energy_needs()

void FatmassEnergyBudget::add_energy_needs

(

const double

energy

)

Increase energy needs.

Parameters

energy

Additional energy needs [MJ/ind]

Exceptions

std::invalid_argument

if energy<0.0

catabolize_fat()

void FatmassEnergyBudget::catabolize_fat

(

)

Burn fat reserves and reduce unmet energy needs.

Fat mass never drops below zero.

force_body_condition()

void FatmassEnergyBudget::force_body_condition

(

const double

body_condition

)

Set the proportional fat reserves.

Parameters

body_condition

Current fat mass divided by potential maximum fat mass.

Exceptions

std::invalid_argument

If body_condition not in interval [0,1]

get_energy_needs()

double Fauna::FatmassEnergyBudget::get_energy_needs ( ) const

inline

Current energy needs [MJ/ind].

get_fatmass()

double Fauna::FatmassEnergyBudget::get_fatmass ( ) const

inline

Current fat mass [kg/ind].

get_max_anabolism_per_day()

double FatmassEnergyBudget::get_max_anabolism_per_day

(

)

const

Get the maximum energy [MJ/ind/day] that could be anabolized in a day.

get_max_fatmass()

double Fauna::FatmassEnergyBudget::get_max_fatmass ( ) const

inline

Maximum fat mass [kg/ind].

merge()

void FatmassEnergyBudget::merge	(	const FatmassEnergyBudget &	other,
		const double	this_weight,
		const double	other_weight
	)

Merge this object with another one by building weighted averages.

Parameters

other	The other object.
this_weight	Weight for this object.
other_weight	Weight for the other object.

metabolize_energy()

void FatmassEnergyBudget::metabolize_energy

(

double

energy

)

Update budget and fat mass by receiving energy (through feeding)

If energy exceeds current energy needs, the surplus is stored as fat (anabolism).

Parameters

energy

Input energy [MJ/ind].

Exceptions

std::invalid_argument	If energy<0.0.
std::logic_error	if energy exceeds current energy needs and maximum anabolism.

set_max_fatmass()

void FatmassEnergyBudget::set_max_fatmass	(	const double	max_fatmass,
		const double	max_gain
	)

Set the maximum allowed fat mass [kg/ind] and fat gain [kg/ind/day].

Parameters

max_fatmass	Current maximum fat mass [kg/ind].
max_gain	Maximum fat mass gain [kg/ind/day]. A value of zero indicates no limit.

Exceptions

std::logic_error	if max_fatmass is smaller than current fat mass
std::invalid_argument	If max_fatmass<=0.0 or if max_gain < 0.

Member Data Documentation

anabolism_coefficient

double Fauna::FatmassEnergyBudget::anabolism_coefficient

private

catabolism_coefficient

double Fauna::FatmassEnergyBudget::catabolism_coefficient

private

energy_needs

double Fauna::FatmassEnergyBudget::energy_needs = 0.0

private

fatmass

double Fauna::FatmassEnergyBudget::fatmass

private

max_fatmass

double Fauna::FatmassEnergyBudget::max_fatmass

private

max_fatmass_gain

double Fauna::FatmassEnergyBudget::max_fatmass_gain = 0.0

private

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The documentation for this class was generated from the following files:

• /home/docs/checkouts/readthedocs.org/user_builds/modular-megafauna-model/checkouts/latest/src/Fauna/fatmass_energy_budget.h
• /home/docs/checkouts/readthedocs.org/user_builds/modular-megafauna-model/checkouts/latest/src/Fauna/fatmass_energy_budget.cpp