computeCatch {FLCore} | R Documentation

## Methods to compute total catch, landings, discards and stock biomass

### Description

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 discards, landings 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

landings = landings.n * landings.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 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 elements names `catch`, `catch.n` and `catch.wt`, which can then be passed directly to the `catch<-` replacement method.

### Generic function

computeCatch(object, ...)

computeLandings(object, ...)

computeDiscards(object, ...)

computeStock(object, ...)

### Method arguments

`object` :
  an object of a class for which this method has been defined.
`slot` :
  a character vector to select the calculation to perform in `computeCatch`. One of "n", "wt", "all" or "catch", the default value. The later will compute the total catch (for slot `catch`) from `catch.n` and `catch.wt`
`na.rm` :
  a logical indicating whether `NA`s should be deleted from the sums. Defaults to `TRUE`.

### Methods

signature(object=FLCatch) :
  computation on an `FLCatch` object.
signature(object=FLStock) :
  computation on an `FLStock` object.
signature(object=FLIndex) :
  computation on an `FLIndex` object.

### Author(s)

The FLR Team

### See Also

FLComp

### Examples

    data(ple4)
    summary(computeLandings(ple4))
    landings(ple4) <- computeLandings(ple4)
    catch(ple4) <- computeCatch(ple4, slot="all")

[Package FLCore version 2.2 Index]