The five-parameter growth function from Schnute and Richards (1990).
The five-parameter growth function from Schnute and Richards (1990). Note that this function is slightly modified (a ‘+’ was changed to a ‘-’ so that the ‘a’ parameter will be positive) from the original in Schnute and Richards (1990)
SchnuteRichards(t, Linf = NULL, k = NULL, a = NULL, b = NULL, c = NULL)
t |
A numeric vector of ages over which to model growth. |
Linf |
Mean asymptotic length. |
k |
The "growth coefficient" with units of (year^(-c)). |
a |
A dimensionless parameter |
b |
A dimensionless parameter. |
c |
A dimensionless parameter. |
SchnuteRichards returns a predicted size given the provided parameter values.
None specifically, but 12-Individual Growth is related.
Derek H. Ogle, derek@derekogle.com
Schnute, J.T. and L.J. Richards. 1990. A unified approach to the analysis of fish growth, maturity, and survivorship data. Canadian Journal of Fisheries and Aquatic Sciences. 47:24-40.
See vbFuns, GompertzFuns, RichardsFuns, logisticFuns, and Schnute for similar functionality for other models.
## See the formulae
growthFunShow("SchnuteRichards",plot=TRUE)
## Simple examples
ages <- 1:15
s1 <- SchnuteRichards(ages,Linf=100,k=0.03,a=0.01,b=0.005,c=2)
plot(s1~ages,type="l",lwd=2)Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.