calc_SSB {LeMaRns}

Calculate Spawning Stock Biomass (SSB) or total biomass

Description

Calculates the spawning stock biomass (SSB) or total biomass of each species in the model.

Usage

calc_SSB(wgt, mature, N)

calc_biomass(wgt, N)

Arguments

wgt

A matrix with dimensions nsc and nfish representing the weight of each species in each length class.

mature

A matrix with dimensions ncs and nfish with elements in the range 0-1 representing the proportion of mature individuals of each species in each length class.

N

A matrix with dimensions nsc and nfish representing the number of individuals in each length class for the current time step.

Details

The Spawning Stock Biomass is equal to colSums(mature*N*wgt) and the total biomass is equal to colSums(mature*N*wgt).

Value

calc_SSB returns a numeric vector of length nfish representing the SSB of each species (g).

calc_biomass returns a numeric vector of length length(species) where the jth element is the biomass (g) of the jth species.

See Also

calc_recruits

Examples

# Set up and run the model
NS_params <- LeMansParam(NS_par, tau=NS_tau, eta=rep(0.25, 21), L50=NS_par$Lmat, other=1e12)
effort <- matrix(0.5, 10, dim(NS_params@Qs)[3])
model_run <- run_LeMans(NS_params, years=10, effort=effort)

# Calculate SSB
calc_SSB(wgt=NS_params@wgt, mature=NS_params@mature, N=model_run@N[,,101])

# Calculate biomass in the last time step
calc_biomass(wgt=NS_params@wgt, N=model_run@N[,,101])