F_a_min: F_a_min

In polehalieutique/demerstem: This package aims to falicitate Fish stock assessement for west african partners involved in the EU DEMERSTEM project

F_a_min

Description

F_a_min function to be optimized by stats::optimize, hence gives an estimation by iteration of F minimum value

Usage

F_a_min(x)

Examples

Mat_Cage <- apply(Mat_C, 1, sum) # catch sum by age over fleets
Mat_M <- rep(0.2, age)
age <- length(Mat_M) # number of age class
Mat_N2 <- rep(NA,age) # initial abundance
nbflot <- length(Mat_C) # number of gear
assign('nbflot', nbflot, envir=globalenv())
Mat_q <- Mat_C #initialisation des capturabilites par les captures
indice <- 1 # age de recrutement
# furst calcul of F, q and N from R, C, E and M.
Mat_F2 <- Mat_C/Mat_Cage #  initialisation of F with a ration by gear
indice <- 1
assign('indice', 1, envir=globalenv())
Mat_N2[indice] <- Rinit
assign('Mat_N2', Mat_N2, envir=globalenv())
Mat_F2[indice,] <- Mat_F2[indice,]*optimize(F_a_min, interval=c(0,2))$minimum

polehalieutique/demerstem documentation built on Aug. 4, 2024, 5:12 a.m.