R: readParameters

readParameters {irace} | R Documentation

## readParameters

### Description

`readParameters` reads the parameters to be tuned by irace from a file or directly from a character string.

### Usage

    readParameters(file, digits = 4, debugLevel = 0, text)

### Arguments

`file` | (`character(1)`) Filename containing the definitions of the parameters to be tuned.
`digits` | The number of decimal places to be considered for the real parameters.
`debugLevel` | (`integer(1)`) Larger values produce more verbose output.
`text` | (`character(1)`) If `file` is not supplied and this is, then parameters are read from the value of `text` via a text connection.

### Details

Either `file` or `text` must be given. If `file` is given, the parameters are read from the file `file`. If `text` is given instead, the parameters are read directly from the `text` character string. In both cases, the parameters must be given (in `text` or in the file whose name is `file`) in the expected form. See the documentation for details. If none of these parameters is given, irace will stop with an error.

A fixed parameter is a parameter that should not be sampled but instead should be always set to the only value of its domain. In this function we set isFixed to TRUE only if the parameter is a categorical and has only one possible value. If it is an integer and the minimum and maximum are equal, or it is a real and the minimum and maximum values satisfy `round(minimum, digits) == round(maximum, digits)`, then the parameter description is rejected as invalid to identify potential user errors.

### Value

A list containing the definitions of the parameters read. The list is structured as follows:

`names`

  Vector that contains the names of the parameters.

`types`

  Vector that contains the type of each parameter 'i', 'c', 'r', 'o'. Numerical parameters can be sampled in a log-scale with 'i,log' and 'r,log' (no spaces).

`switches`

  Vector that contains the switches to be used for the parameters on the command line.

`domain`

  List of vectors, where each vector may contain two values (minimum, maximum) for real and integer parameters, or possibly more for categorical parameters.

`conditions`

  List of R logical expressions, with variables corresponding to parameter names.

`isFixed`

  Logical vector that specifies which parameter is fixed and, thus, it does not need to be tuned.

`nbParameters`

  An integer, the total number of parameters.

`nbFixed`

  An integer, the number of parameters with a fixed value.

`nbVariable`

  Number of variable (to be tuned) parameters.

### Author(s)

Manuel López-Ibáñez and Jérémie Dubois-Lacoste

### Examples

     ## Read the parameters directly from text
     parameters.table <- '
     # name       switch           type values               [conditions (using R syntax)]
     algorithm    "--"             c    (as,mmas,eas,ras,acs)
     localsearch  "--localsearch " c    (0, 1, 2, 3)
     alpha        "--alpha "       r    (0.00, 5.00)
     beta         "--beta "        r    (0.00, 10.00)
     rho          "--rho  "        r    (0.01, 1.00)
     ants         "--ants "        i            (5, 100)
     q0           "--q0 "          r    (0.0, 1.0)           | algorithm == "acs"
     rasrank      "--rasranks "    i    (1, 100)             | algorithm == "ras"
     elitistants  "--elitistants " i    (1, 750)             | algorithm == "eas"
     nnls         "--nnls "        i    (5, 50)              | localsearch %in% c(1,2,3)
     dlb          "--dlb "         c    (0, 1)               | localsearch %in% c(1,2,3)
     '
     parameters <- readParameters(text=parameters.table)
     str(parameters)

[Package irace version 3.4.1 Index]