On Sep 19, 2010, at 9:41 AM, Goran Jovic wrote: > Anyway, being a Clojure newbie myself, I had a huge benefit from > freely available code examples, so I decided to share my own project > with other folks who are learning Clojure. > > It's hosted on: > http://code.google.com/p/genetic-my-number/ > > So, enjoy... and, of course, I always welcome ideas, suggestions, > (constructive) criticism or any other comments.
Perhaps you'd be interested in a related but slightly different approach to solving a related but slightly different problem. The problem is the one posed by the numeric card game Krypto ( http://en.wikipedia.org/wiki/Krypto_(game) ), and the solution uses not a standard genetic algorithm but rather a genetic programming system (Clojush, a Clojure implementation of Push/PushGP). Using this to solve Krypto, which is quite simple, is a bit like using a sledgehammer to kill a fly, but it made a cute little exercise so I included it as one of the examples in the latest version of the Clojush system: http://github.com/lspector/Clojush BTW I mentioned the Clojush project here previously but I've recently made a number of significant improvements based on comments I received. It's much more idiomatic Clojure code now, although I'm sure it still bears traces of its history in Common Lisp and Scheme. Also, just for kicks I recently wrote Clojure code to solve Krypto instances directly, since it's pretty easy. I'll paste in the code below. People will yell that I shouldn't use eval or non-recur recursive calls, but I think they're fine in this (toy) case. -Lee ;; kryptosolve.clj ;; Clojure code for solving instances of the game of Krypto. ;; See http://en.wikipedia.org/wiki/Krypto_(game) ;; Lee Spector, lspec...@hampshire.edu, 2010 (ns kryptosolve (:use clojure.contrib.combinatorics)) (defn safe-eval "Returns the result of evaluating e, or :error if it throws an exception." [e] (try (eval e) (catch java.lang.Exception _ :error))) (defn all-splits "Returns a sequence of all ways of splitting values into 2 subsequences." [values] (map #(split-at (inc %) values) (range (dec (count values))))) (defn expressions "Returns a sequence of all of the arithmetic expressions that can be formed with the provided values in the given order." [values] (if (< (count values) 2) values (mapcat (fn [[left-values right-values]] (mapcat (fn [[left-expression right-expression]] (map #(list % left-expression right-expression) '(+ - * /))) (cartesian-product (expressions left-values) (expressions right-values)))) (all-splits values)))) (defn solve-krypto "Returns a solution expression if one can be found for the given values and target." [values target] (first (filter #(= (safe-eval %) target) (mapcat expressions (lex-permutations values))))) (solve-krypto [1 2 3 4 5] 25) -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
