PBSmodelling (version 2.68.8)

scalePar: Scale Parameters to [0,1]

Description

Scale parameters for function minimization by calcMin.

Usage

scalePar(pvec)

Value

Parameter vector scaled between 0 and 1.

Arguments

pvec

a data frame comprising four columns - c("val","min","max","active") and as many rows as there are model parameters. The "active" field (logical) determines whether the parameters are estimated (TRUE) or remain fixed (FALSE).

Author

Jon T. Schnute, Pacific Biological Station, Fisheries and Oceans Canada, Nanaimo BC

Details

Scaling algorithm: \( S = \frac{2}{\pi} asin \sqrt{ \frac{P - P_{min}}{P_{max} - P_{min}} } \)

See Also

restorePar, calcMin, GT0

Examples

local(envir=.PBSmodEnv,expr={
  pvec <- data.frame(val=c(1,100,10000),min=c(0,0,0),max=c(5,500,50000),
    active=c(TRUE,TRUE,TRUE))
  S    <- scalePar(pvec)
  print(cbind(pvec,S))
})