FLFleet-class: Class FLFleet

In FLCore: Core package of FLR, fisheries modelling in R.

Description

The FLFleet class is a composite object storing some useful information for the description and analysis of fleet data, including basic information about effort and economic data. It can account for simple or complex patterns such as several types of activities and/or catches of several species.

FLFleet is thus defined along a three-levelled tree structure. First, the root of FLFleet contains data at the vessel/fleet segment levels, independent of activity and catches, such as total effort, capacity, fixed costs and crew share. Then, data dealing with the various types of activity of the fleet are dealt with at the metier level using FLMetier class, which includes slots for proportion of effort and variable costs.

Finally, the cath information related to the various species or stocks within each metier are dealt with a FLCatch class. The tree structure allows a flexible use of the FLFleet object, if for example not all species are caught by all metiers or if the dimensions are not the same across branches.

There is a certain degree of flexibility left in the slots definition, in the sense that the user may decide to store either raw unit data, for example effort by unit of capacity, variable cost by unit of effort, or to store aggregated data, for example total effort or total variable costs. However, the user should be aware that some computing methods (in FLCore or other related packages) are more specifically intended for one type of data, and these should be used with caution.

A number of accessors are defined for FLFleet, allowing to extract directly specific slots at the three-levels FLFleet hierarchy i.e. from the FLFleet class itself, from the FLMetier objects and from the FLCatch objects it contains.

If both catch and metier arguments are specified in those, it returns the FLQuant corresponding to the species. If catch argument is missing but metier argument is specified, it returns a FLQuants object for all stocks of the FLCatches object for the given specified metier. Finally, if catch argument is specified but metier argument is missing, it returns a FLQuants object across all metiers of the FLMetiers object for the given specified species.

Corresponding replacement methods for these slots exist for the FLQuant objects but not for the FLQuants objects, due to possible differences of dimensions across FLMetier and FLCatch objects.

Slots

effort

effort (total or per unit of capacity). FLQuant.

fcost

Fixed costs (total or per unit of capacity). FLQuant.

capacity

Capacity of the fleet. FLQuant.

crewshare

Crew share (total or per unit of capacity). FLQuant.

metiers

FLMetiers object storing a list of FLMetier objects. FLMetiers.

name

Generic name slot inherited from FLComp class. character.

desc

Generic description slot inherited from FLComp class. character.

range

Generic range slot inherited from FLComp class indicating min quant, max quant, plusgroup quant,minyear and maxyear. numeric.

Extends

FLComp

Constructor

The FLFleet(object) constructor method allows simple creation of new FLCatch with the methods described below.

signature(object=FLMetiers) :

create a FLFleet object from a FLMetiers object

signature(object=FLMetier) :

create a FLFleet object from a FLMetier object

signature(object=FLCatches) :

create a FLFleet object from a FLCatches object

signature(object=FLCatch) :

create a FLFleet object from a FLCatch object

signature(object=FLQuant) :

create a FLFleet object from a FLQuant object

signature(object=missing) :

create a void FLFleet object for future use

Methods

catch(FLCore) :

Accessor method for the catch slot across FLMetiers and FLCatches objects

signature(object=missing)

catch.n(FLCore) :

Accessor method for the catch.n slot across FLMetiers and FLCatches objects

signature(object=missing)

catch.wt(FLCore) :

Accessor method for the catch.wt slot across FLMetiers and FLCatches objects

signature(object=missing)

catch.sel(FLCore) :

Accessor method for the catch.sel slot across FLMetiers and FLCatches objects

signature(object=missing)

catch.q(FLCore) :

Accessor method for the catch.q slot across FLMetiers and FLCatches objects

signature(object=missing)

discards(FLCore) :

Accessor method for the discards slot across FLMetiers and FLCatches objects

signature(object=missing)

discards.n(FLCore) :

Accessor method for the discards.n slot across FLMetiers and FLCatches objects

signature(object=missing)

discards.sel(FLCore) :

Accessor method for the discards.sel slot across FLMetiers and FLCatches objects

signature(object=missing)

discards.wt(FLCore) :

Accessor method for the discards.wt slot across FLMetiers and FLCatches objects

signature(object=missing)

landings(FLCore) :

Accessor method for the landings slot across FLMetiers and FLCatches objects

signature(object=missing)

landings.n(FLCore) :

Accessor method for the landings.n slot across FLMetiers and FLCatches objects

signature(object=missing)

landings.wt(FLCore) :

Accessor method for the landings.wt slot across FLMetiers and FLCatches objects

signature(object=missing)

landings.sel(FLCore) :

Accessor method for the landings.sel slot across FLMetiers and FLCatches objects

signature(object=missing)

price(FLCore) :

Accessor method for the price slot across FLMetiers and FLCatches objects

signature(object=missing)

coerce(methods) :

coerces a FLStock object into a FLFleet object. This method is called by typing as(x,"FLFleet"). This will first coerce the FLStock object into a FLCatch object, with catch.q equal to 1, and then create a FLFleet object with an effort slot equal to max(harvest(x)) so that back calculation of harvest as the product of effort, catchability and selectivity is consistent with harvest(x).

signature(from=NULL,to=FLFleet,strict=missing)

iter(FLCore) :

return the ith iteration of a FLFleet object. The value is of class FLFleet also.

signature(object="FLFleet")

revenue(FLCore) :

describe...

signature(fill...)

signature(fill...)

summary(base) :

returns the summary of the FLFleet object

signature(fill...)

Author(s)

The FLR Team

See Also

catch, catch.n, catch.wt, catch.sel,catch.q, coerce, discards, discards.n, discards.sel, discards.wt, landings, landings.n, landings.sel, landings.wt, price, FLComp

Examples

# creating objects
my.fleet <- FLFleet(name='fleet1',metiers=FLMetiers(FLMetier(name='met1',catches=FLCatches(FLCatch()))))
my.fleet <- FLFleet(FLMetier(name='met1',catches=FLCatches(FLCatch())))
my.fleet <- FLFleet(FLCatches(FLCatch())) # a metier is implicitely created
my.fleet <- FLFleet(FLCatch()) # a metier is implicitely created
my.fleet <- FLFleet()

# in house example
data(bt4)

catch(bt4, catch="PLE")   # returns a FLQuants object across metiers
catch(bt4,met="TBB")   # returns a FLQuants object across catches
catch(bt4,met="TBB", catch="ple") # returns a FLQuant

effort(bt4) # a FLFleet slot
effshare(bt4@metiers[[1]]) # a FLMetier slot for metier 1
# => metier(bt4,met="OTH") is missing...exist but not in the NAMESPACE?
catch(bt4@metiers[[1]]@catches[[1]]) # a FLCatch slot for metier 1 and catch 1

FLCore documentation built on May 2, 2019, 5:46 p.m.