rowan.a.tl/propeller
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Make lexicase-selection use provided :initial-cases and return :selection-cases, both via argmap

Browse Source
This commit is contained in:
Lee Spector 2023-12-02 17:35:14 -05:00
parent d0d0427dcf
commit 30a87a2688
1 changed files with 12 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

22
src/propeller/selection.cljc
View File

@ -19,16 +19,18 @@
eliminating any individuals with errors for the current case that are worse than the best error in the selection pool,
until a single individual remains."
[pop argmap]
(loop [survivors (map rand-nth (vals (group-by :errors pop)))
cases (shuffle (range (count (:errors (first pop)))))]
(if (or (empty? cases)
(empty? (rest survivors)))
(rand-nth survivors)
(let [min-err-for-case (apply min (map #(nth % (first cases))
(map :errors survivors)))]
(recur (filter #(= (nth (:errors %) (first cases)) min-err-for-case)
survivors)
(rest cases))))))
(let [initial-cases (or (:initial-cases argmap)
(shuffle (range (count (:errors (first pop))))))]
(loop [survivors (map rand-nth (vals (group-by :errors pop)))
cases initial-cases]
(if (or (empty? cases)
(empty? (rest survivors)))
(assoc (rand-nth survivors) :selection-cases initial-cases)
(let [min-err-for-case (apply min (map #(nth % (first cases))
(map :errors survivors)))]
(recur (filter #(= (nth (:errors %) (first cases)) min-err-for-case)
survivors)
(rest cases)))))))
(defn fitness-proportionate-selection
"Selects an individual from the population using a fitness proportionate selection."