This is a R implementation of a systematic search, where the fuzzy set positions are determined
by the distribution of the data (cf compute_optimal_quantile_fuzzy_set_positions() and the rules
are systematically explored
fuzzy_coco_systematic_fit(x, y, params, fitter)the input variables data (usually to fit) as a dataframe
the output variables data (usually to fit) as a dataframe
fuzzy coco parameters, as a recursive named list, cf params()
a function metrics –> fitness value providing the objective/fitness function to optimize TODO: describe the metrics
a list of the best results (all ties). Each result is also a named list(metric=,fs=) holding the corresponding metric value and the fuzzy system.