Methods to compute total quant-aggregated catch, landings, discards and stock biomass from age or length-structured numbers and mean weights.
computeLandings(object, ...) computeDiscards(object, ...) computeCatch(object, ...) computeStock(object, ...) # S4 method for FLS computeLandings(object, na.rm = TRUE) # S4 method for FLS computeDiscards(object, na.rm = TRUE) # S4 method for FLS computeCatch(object, slot = "catch", na.rm = TRUE) # S4 method for FLS computeStock(object, na.rm = TRUE)
These methods compute the total catch, landings, discards and stock biomass
from the quant-structured values in numbers and weight per individual. The
calculation for landings, discards and stock involves the product of the
landings/discards/stock in numbers (landings.n
, discards.n
or
stock.n
) by the individual weight-at-quant (landings.wt
,
discards.wt
or stock.wt
), as in
$$L=L_n * L_{wt}$$
By selecting slot="catch"
, computeCatch
can calculate in the
same way the total catch from the catch-at-quant and weight in the catch.
Those two values (in slots catch.n
and catch.wt
) can also be
calculated (from landings and discards) by specifying slot="n"
and
slot="wt"
respectively. Calling computeCatch
with option
slot="all"
will carry out the three calculations. In this case, the
returned object will be of class FLQuants
, with element names
catch
, catch.n
and catch.wt
, which can then be passed
directly to the catch<-
replacement method.
computeCatch(object, ...)
computeLandings(object, ...)
computeDiscards(object, ...)
computeStock(object, ...)
data(ple4) summary(computeLandings(ple4))#> An object of class "FLQuant" with: #> dim : 1 52 1 1 1 1 #> quant: age #> units: t #> #> Min : 48874 #> 1st Qu.: 81541.75 #> Mean : 108403.7 #> Median : 110466 #> 3rd Qu.: 132758.5 #> Max : 169818 #> NAs : 0 %summary(computeCatch(ple4, slot="all"))#> An object of class "FLQuants" #> #> Elements: catch.wt catch.n catch #> #> Name: catch.wt #> dim : 10 52 1 1 1 1 #> quant: age #> units: kg #> #> Min : 0.034 #> 1st Qu.: 0.2206675 #> Mean : 0.4551756 #> Median : 0.4372537 #> 3rd Qu.: 0.6629051 #> Max : 1.108295 #> NAs : 0 % #> Name: catch.n #> dim : 10 52 1 1 1 1 #> quant: age #> units: 1000 #> #> Min : 412 #> 1st Qu.: 7027.75 #> Mean : 81702.88 #> Median : 29044 #> 3rd Qu.: 101951.5 #> Max : 1459325 #> NAs : 0 % #> Name: catch #> dim : 1 52 1 1 1 1 #> quant: age #> units: t #> #> Min : 78422.95 #> 1st Qu.: 126077.3 #> Mean : 165127 #> Median : 151975.4 #> 3rd Qu.: 182754.8 #> Max : 342985.1 #> NAs : 0 %