baranov.cpp File Reference

Routines for iteratively solving the Baranov catch equation. More...

#include "statsLib.h"

Go to the source code of this file.

## Functions

double get_ft (const double &ct, const double &m, const dvector &va, const dvector &ba)
dvector get_ft (dvector &ct, const double &m, const dmatrix &V, const dvector &ba)
Solving the Baranov catch equation for multiple fleets.
dvector get_ft (dvector &ct, const double &m, const dmatrix &V, const dvector &na, const dvector &wa)
Solving the Baranov catch equation for multiple fleets.

## Detailed Description

Routines for iteratively solving the Baranov catch equation.

Date:
2/28/2011

The general form of the Baranov catch equation is given by:

where is the catch (in either total numbers or total weight) is the abundance at the start of the time step, is the instantaneous fishing mortality rate is the instantaneous natural mortality rate. The Baranov catch equation is a transcedental equation; here Newtons root finding method is implemented to determine .

The basic algorithm is as follows:

1) Set initial guess for based on Popes approximation .

2) Calculate the predicted catch based on initial

3) Calculate the derivative of the catch equation

4) Update estimate of using

At present this function is only implemented for data-type variables.

Definition in file baranov.cpp.

## Function Documentation

 double get_ft ( const double & ct, const double & m, const dvector & va, const dvector & ba )
Date:
2011-07-12
Parameters:
 ct the observed catch m the instantaneous natural mortality rate va a vector of age-specific selectivities. ba the initial numbers or biomass (same units as the catch) at age.
Returns:
ft the instantaneous fishing mortality rate for fully selected (va=1) individuals.

Definition at line 51 of file baranov.cpp.

 dvector get_ft ( dvector & ct, const double & m, const dmatrix & V, const dvector & ba )

Solving the Baranov catch equation for multiple fleets.

Date:
2011-07-12
Parameters:
 ct a vector of observed catch for each fleet. m the instantaneous natural mortality rate (age-independent). V a matrix of age-specific selectivities where each row corresponds to the fleet. ba the initial numbers or biomass (same units as the catch) at age.
Returns:
ft a vector of instantaneous fishing mortality rate for fully selected (va=1) individuals for each fishing fleet.

Definition at line 94 of file baranov.cpp.

 dvector get_ft ( dvector & ct, const double & m, const dmatrix & V, const dvector & na, const dvector & wa )

Solving the Baranov catch equation for multiple fleets.

Date:
2011-07-12
Parameters:
 ct a vector of observed catch for each fleet. m the instantaneous natural mortality rate (age-independent). V a matrix of age-specific selectivities where each row corresponds to the fleet. na a vector of initial numbers or biomass (same units as the catch) at age. wa a vector of mean weights-at-age
Returns:
ft a vector of instantaneous fishing mortality rate for fully selected (va=1) individuals for each fishing fleet.