gnlsControl {nlme} | R Documentation

## Control Values for gnls Fit

### Description

The values supplied in the function call replace the defaults and a list with all possible arguments is returned. The returned list is used as the `control` argument to the `gnls` function.

### Usage

    gnlsControl(maxIter, nlsMaxIter, msMaxIter, minScale, tolerance,
                nlsTol, msTol, returnObject, msVerbose,
                apVar, .relStep,
                opt = c("nlminb", "optim"), optimMethod,
                minAbsParApVar, sigma = NULL)

### Arguments

`maxIter` | maximum number of iterations for the `gnls` optimization algorithm. Default is 50.
`nlsMaxIter` | maximum number of iterations for the `nls` optimization step inside the `gnls` optimization. Default is 7.
`msMaxIter` | maximum number of iterations for the `ms` optimization step inside the `gnls` optimization. Default is 50.
`minScale` | minimum factor by which to shrink the default step size in an attempt to decrease the sum of squares in the `nls` step. Default 0.001.
`tolerance` | tolerance for the convergence criterion in the `gnls` algorithm. Default is 1e-6.
`nlsTol` | tolerance for the convergence criterion in `nls` step. Default is 1e-3.
`msTol` | tolerance for the convergence criterion of the first outer iteration when `optim` is used. Default is 1e-7.
`returnObject` | a logical value indicating whether the fitted object should be returned when the maximum number of iterations is reached without convergence of the algorithm. Default is `FALSE`.
`msVerbose` | a logical value passed as the `trace` argument to `ms` (see documentation on that function). Default is `FALSE`.
`apVar` | a logical value indicating whether the approximate covariance matrix of the variance-covariance parameters should be calculated. Default is `TRUE`.
`.relStep` | relative step for numerical derivatives calculations. Default is `.Machine$double.eps^(1/3)`.
`opt` | the optimizer to be used, either `"nlminb"` (the current default) or `"optim"` (the previous default).
`optimMethod` | character - the optimization method to be used with the `optim` optimizer. The default is `"BFGS"`. An alternative is `"L-BFGS-B"`.
`minAbsParApVar` | numeric value - minimum absolute parameter value in the approximate variance calculation. The default is `0.05`.
`sigma` | optionally a positive number to fix the residual error at. If `NULL`, as by default, or `0`, sigma is estimated.

### Value

a list with components for each of the possible arguments.

### Author(s)

José Pinheiro and Douglas Bates bates@stat.wisc.edu; the `sigma` option: Siem Heisterkamp and Bert van Willigen.

### See Also

`gnls`

### Examples

    # decrease the maximum number iterations in the ms call and
    # request that information on the evolution of the ms iterations be printed
    gnlsControl(msMaxIter = 20, msVerbose = TRUE)

[Package nlme version 3.1-131 Index]