#lang racket ;;; Science Collection ;;; random-distributions/gaussian-graphics.rkt ;;; Copyright (c) 2004-2011 M. Douglas Williams ;;; ;;; This file is part of the Science Collection. ;;; ;;; The Science Collection is free software: you can redistribute it and/or ;;; modify it under the terms of the GNU Lesser General Public License as ;;; published by the Free Software Foundation, either version 3 of the License ;;; or (at your option) any later version. ;;; ;;; The Science Collection is distributed in the hope that it will be useful, ;;; but WITHOUT WARRANTY; without even the implied warranty of MERCHANTABILITY ;;; or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public ;;; License for more details. ;;; ;;; You should have received a copy of the GNU Lesser General Public License ;;; along with the Science Collection. If not, see ;;; <http://www.gnu.org/licenses/>. ;;; ;;; ------------------------------------------------------------------- ;;; ;;; This code implements graphics for Gaussian distributions. ;;; ;;; Version Date Description ;;; 0.1.0 08/07/04 This is the initial release of the Guassian ;;; distribution graphics routines. (Doug Williams) ;;; 1.0.0 09/28/04 Added contracts for functions. Marked as ready ;;; for Release 1.0. (Doug Williams) ;;; 2.0.0 11/19/07 Changed calls to unchecked versions. ;;; (Doug Williams) ;;; 3.0.0 06/09/08 Changes required for V4.0 (Doug Williams) ;;; 3.0.1 07/01/08 Changed x axis label. (Doug Williams) ;;; 4.0.0 08/16/11 Changed the header and restructured the code. (MDW) (require "gaussian.ss" plot) ;;; gaussian-plot: real x real -> void ;;; Plot the pdf and cdf for a gaussian distribution with the given ;;; mean and standard deviation. The x axis range is +/- three sigma ;;; around the mean. (define (gaussian-plot mu sigma) (plot (mix (line (lambda (x) (unchecked-gaussian-pdf x mu sigma)) #:color 'red) (line (lambda (x) (unchecked-gaussian-cdf x mu sigma)) #:color 'blue)) #:x-min (+ mu (* -3 sigma)) #:x-max (+ mu (* 3 sigma)) #:x-label "X" #:y-min 0 #:y-max 1 #:y-label "Density" #:title "Gaussian Distribution")) ;;; unit-gaussian-plot: -> void ;;; Plot the pdf and cdf for a unit gaussian distribution (standard ;;; normal distribution). The x axis range is +/- three. (define (unit-gaussian-plot) (plot (mix (line unchecked-unit-gaussian-pdf #:color 'red) (line unchecked-unit-gaussian-cdf #:color 'blue)) #:x-min -3 #:x-max 3 #:x-label "X" #:y-min 0 #:y-max 1 #:y-label "Density" #:title "Unit Gaussian Distribution")) ;;; Module Contracts (provide/contract (gaussian-plot (-> real? (>=/c 0.0) any)) (unit-gaussian-plot (-> any)))