bmass-class {FLEDA}R Documentation

Class "bmass" for mature and immature biomass

Description

This class encapsulates results of a mature (mb) and immature (ib) biomass method.

Creating objects from the class

Objects of this classe should be created with a call to the creator function bmass(object, ...), where object must be of class "FLStock" and ... can be used to pass trim arguments to the creator funtion.

Slots

bmass
Object of class "FLQuants" with a mb component and a ib component.

Extends

Class "FLQuants", directly.

Methods

Inherits from "FLQuants".

Details

Considering C_{ay}, the catch in numbers, W_{ay}, the mean weight and M_{ay}, the proportion of mature fish, at age a=1,...,A and year y=1,...,Y obtained e.g. from a "FLStock" object, the computations of bmass are:

mb:

MB_{y}=sum_{a}{C_{ay}*W_{ay}*M_{ay}}

ib:

IB_{y}=sum_{a}{C_{ay}*W_{ay}*(1-M_{ay})}

See Also

FLQuant-class, trim, logr-class

Examples

data(ple4)
# compute mature and immature biomass
ple4.bmass <- bmass(ple4)
# tune plot
ttl <- list(label="Trends in biomass for mature and immature plaice in IV", cex=1)
yttl <- list(label="relative biomass", cex=0.8)
xttl <- list(cex=0.8)
ax <- list(cex=0.8)
akey <- simpleKey(text=c("mature", "immature"), points=FALSE, lines=TRUE)
# plot
xyplot(data~year, data=ple4.bmass, type="l", main=ttl,
       key=akey, ylab=yttl, xlab=xttl, scales=ax)

[Package FLEDA version 1.4-2 Index]