diff options
Diffstat (limited to 'src/clojure/contrib/probabilities')
| -rw-r--r-- | src/clojure/contrib/probabilities/dist.clj | 23 | ||||
| -rw-r--r-- | src/clojure/contrib/probabilities/dist/examples.clj | 10 |
2 files changed, 19 insertions, 14 deletions
diff --git a/src/clojure/contrib/probabilities/dist.clj b/src/clojure/contrib/probabilities/dist.clj index a5a07c80..21008fc7 100644 --- a/src/clojure/contrib/probabilities/dist.clj +++ b/src/clojure/contrib/probabilities/dist.clj @@ -1,7 +1,7 @@ ;; Finite probability distributions ;; by Konrad Hinsen -;; last updated February 18, 2009 +;; last updated March 2, 2009 ;; Copyright (c) Konrad Hinsen, 2009. All rights reserved. The use ;; and distribution terms for this software are covered by the Eclipse @@ -12,8 +12,9 @@ ;; remove this notice, or any other, from this software. (ns clojure.contrib.probabilities.dist - (:use clojure.contrib.monads clojure.contrib.macros - clojure.contrib.monads clojure.contrib.def)) + (:use [clojure.contrib.monads + :only (defmonad domonad with-monad maybe-t m-lift m-chain)] + [clojure.contrib.def :only (defvar)])) ; The probability distribution monad. It is limited to finite probability ; distributions (e.g. there is a finite number of possible value), which @@ -26,8 +27,8 @@ [m-result (fn m-result-dist [v] {v 1}) m-bind (fn m-bind-dist [mv f] - (letfn-kh [add-prob [dist [x p]] - (assoc dist x (+ (get dist x 0) p))] + (letfn [(add-prob [dist [x p]] + (assoc dist x (+ (get dist x 0) p)))] (reduce add-prob {} (for [[x p] mv [y q] (f x)] [y (* q p)])))) @@ -91,12 +92,12 @@ pairs. In the last pair, the probability can be given by the keyword :else, which stands for 1 minus the total of the other probabilities." [& choices] - (letfn-kh [add-choice [dist [p v]] + (letfn [(add-choice [dist [p v]] (cond (nil? p) dist (= p :else) - (let [total-p (reduce + (vals dist))] - (assoc dist v (- 1 total-p))) - :else (assoc dist v p))] + (let [total-p (reduce + (vals dist))] + (assoc dist v (- 1 total-p))) + :else (assoc dist v p)))] (reduce add-choice {} (partition 2 choices)))) (with-monad dist-m @@ -132,10 +133,10 @@ (with-monad dist-m (defn- select-n [n xs] - (letfn-kh [select-1 [[s xs]] + (letfn [(select-1 [[s xs]] (uniform (for [i (range (count xs))] (let [[nth rest] (nth-and-rest i xs)] - (list (cons nth s) rest))))] + (list (cons nth s) rest)))))] ((m-chain (replicate n select-1)) (list '() xs)))) (defn select [n xs] diff --git a/src/clojure/contrib/probabilities/dist/examples.clj b/src/clojure/contrib/probabilities/dist/examples.clj index 947f5366..17bf401e 100644 --- a/src/clojure/contrib/probabilities/dist/examples.clj +++ b/src/clojure/contrib/probabilities/dist/examples.clj @@ -6,9 +6,13 @@ ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; -(use 'clojure.contrib.probabilities.dist - 'clojure.contrib.monads) -(require 'clojure.contrib.accumulators) +(ns clojure.contrib.probabilities.dist.examples + (:use [clojure.contrib.probabilities.dist + :only (uniform prob cond-prob join-with dist-m choose + normalize certainly cond-dist-m normalize-cond)]) + (:use [clojure.contrib.monads + :only (domonad with-monad m-seq m-chain m-lift)]) + (:require clojure.contrib.accumulators)) ;; Simple examples using dice |