| bmass-class {FLEDA} | R Documentation |
This class encapsulates results of a mature (mb) and immature (ib) biomass method.
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.
"FLQuants" with a mb component and a ib component.
Class "FLQuants", directly.
Inherits from "FLQuants".
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})}
FLQuant-class, trim, logr-class
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)