irace (version 3.1)

ablation: Performs ablation between two configurations.

Description

Ablation is a method for analyzing the differences between two configurations.

Usage

ablation(iraceLogFile = NULL, iraceResults = NULL, src = NULL,
  target = NULL, ab.params = NULL, n.instances = NULL, type = "full",
  seed = 1234567, ablationLogFile = "log-ablation.Rdata", pdf.file = NULL,
  pdf.width = 20, mar = c(12, 5, 4, 1), debugLevel = NULL)

Arguments

iraceLogFile

Log file created by irace, this file must contain the iraceResults object.

iraceResults

Object created by irace and saved in scenario$logFile.

src, target

Source and target configuration IDs. If NULL, then the first configuration ever evaluated is used as source and the best configuration found is used as target.

ab.params

Parameter names to be used for the ablation. They must be in parameters$names.

n.instances

Number of instances to be used for the "full" ablation, if not provided firstTest instances are used.

type

Type of ablation to perform, "full" will execute all instances in the configurations to determine the best performing, "racing" will apply racing to find the best configurations.

seed

Numerical value to use as seed for the random number generation.

ablationLogFile

Log file to save the ablation log.

pdf.file

Prefix that will be used to save the plot file of the ablation results.

pdf.width

Width provided to create the pdf file.

mar

Vector with the margins for the ablation plot.

debugLevel

Integer value. Larger values produce more verbose output. By default, the debugLevel given by the iraceLogFile / iraceResults.

Value

A list containing the following elements:

configurations

Configurations tested in the ablation.

instances

A matrix with the instances used in the experiments. First column has the instances IDs from iraceResults$scenario$instances, second column the seed assigned to the instance.

experiments

A matrix with the results of the experiments (columns are configurations, rows are instances).

scenario

Scenario object with the settings used for the experiments.

trajectory

IDs of the best configurations at each step of the ablation.

best

Best configuration found in the experiments.

References

C. Fawcett and H. H. Hoos. Analysing differences between algorithm configurations through ablation. Journal of Heuristics, 22(4):431<U+2013>458, 2016.

Examples

# NOT RUN {
irace.logfile <- file.path(system.file(package="irace"), "exdata", "sann.rda")
load(irace.logfile)
# Execute ablation between the first and the best configuration found by irace.
ablation(iraceResults = iraceResults, ablationLogFile = NULL)
# Execute ablation between two selected configurations, and selecting only a
# subset of parameters, directly reading the setup from the irace log file.
ablation(iraceLogFile = irace.logfile, src = 1, target = 10,
         ab.params = c("temp"), ablationLogFile = NULL)
# }
# NOT RUN {
# }