mean.lifespan: Method for calculating mean lifespan, given the natural...

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

Description

For an FLBiol object with the natural mortality-at-age present in the object.

Usage

mean.lifespan(x, ...)

Arguments

x	An object of type FLBiol.
...	Extra arguments accepted by each implementation.

Details

Using actuarial definitions for the expected life-span of a given species, for a given survival rate-at-age (natural mortality), we can compute the expected life-span, logL(x), of a species, from a given reference age x, using the following equation:

logL(x) = SUM_1_inf exp(SUM_i=x_x+t m_i)

.

The method accepts objects of class FLBiol of any particular dimension. If the object has a seasonal structure to the population dynamics, then we sum over all seasons to get the yearly survival rate.

Value

An object of class FLQuant whose first and second dimension is of length one.

Author(s)

FLR Team

See Also

FLBiol

Examples

## Not run: 
data(ple4biol)
lfs.ple4 <- mean.lifespan(ple4,ref.age=1)

## End(Not run)

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