getConvergenceTimes: Get convergence times

Description

Get the convergence times of the different runs of the given search applied to the given problem (in milliseconds). This is a generic S3 method.

Usage

getConvergenceTimes(data, problem, search, r = 0.99)

Arguments

data

data object containing the analysis results

problem

name of the analyzed problem. Can be omitted if the data contains results for a single problem only.

name of the applied search. Can be omitted if the data contains results for a single search only (for the considered problem).

convergence ratio. Defaults to 0.99. Numeric value in [0,1].

Value

Numeric vector containing the convergence times of each run (in milliseconds). All convergence times are greater than or equal to -1.

Details

If the data contains results for a single problem only, the argument problem can be omitted. Likewise, if for the considered problem results are available for a single search only, the argument search can be omitted.

The convergence time of a search run is defined as the time at which a certain value threshold is crossed. This threshold is computed from the given convergence ratio r as follows: if values are being maximized, thr = (1-r)*min + r*max; else, thr = (1-r)*max + r*min, where min and max are the minimum and maximum observed value in the considered search run, respectively. In case of maximization, a search run is said to have converged as soon as it reaches a value which is larger than or equal to the threshold thr. In case of minimization, convergence occurs when the values drop below the threshold. The convergence ratio r defaults to 0.99. If set to 1, a search run is said to have converged when the final best solution is found.