| /* |
| * [The "BSD licence"] |
| * Copyright (c) 2005-2008 Terence Parr |
| * All rights reserved. |
| * |
| * Conversion to C#: |
| * Copyright (c) 2008-2009 Sam Harwell, Pixel Mine, Inc. |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * 3. The name of the author may not be used to endorse or promote products |
| * derived from this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
| * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
| * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| namespace Antlr.Runtime.Misc { |
| using System.Collections.Generic; |
| using Antlr.Runtime.JavaExtensions; |
| |
| using Math = System.Math; |
| |
| /** <summary>Stats routines needed by profiler etc...</summary> |
| * |
| * <remarks> |
| * note that these routines return 0.0 if no values exist in the X[] |
| * which is not "correct", but it is useful so I don't generate NaN |
| * in my output |
| * </remarks> |
| */ |
| public class Stats { |
| public const string ANTLRWORKS_DIR = "antlrworks"; |
| |
| /** <summary>Compute the sample (unbiased estimator) standard deviation following:</summary> |
| * |
| * <remarks> |
| * Computing Deviations: Standard Accuracy |
| * Tony F. Chan and John Gregg Lewis |
| * Stanford University |
| * Communications of ACM September 1979 of Volume 22 the ACM Number 9 |
| * |
| * The "two-pass" method from the paper; supposed to have better |
| * numerical properties than the textbook summation/sqrt. To me |
| * this looks like the textbook method, but I ain't no numerical |
| * methods guy. |
| * </remarks> |
| */ |
| public static double Stddev(int[] X) { |
| int m = X.Length; |
| if (m <= 1) { |
| return 0; |
| } |
| double xbar = EnumerableExtensions.Average(X); |
| double s2 = 0.0; |
| for (int i = 0; i < m; i++) { |
| s2 += (X[i] - xbar) * (X[i] - xbar); |
| } |
| s2 = s2 / (m - 1); |
| return Math.Sqrt(s2); |
| } |
| public static double Stddev(List<int> X) { |
| int m = X.Count; |
| if (m <= 1) { |
| return 0; |
| } |
| double xbar = EnumerableExtensions.Average(X); |
| double s2 = 0.0; |
| for (int i = 0; i < m; i++) { |
| s2 += (X[i] - xbar) * (X[i] - xbar); |
| } |
| s2 = s2 / (m - 1); |
| return Math.Sqrt(s2); |
| } |
| |
| #if DEBUG |
| /** <summary>Compute the sample mean</summary> */ |
| [System.Obsolete] |
| public static double avg(int[] X) { |
| return EnumerableExtensions.Average(EnumerableExtensions.DefaultIfEmpty(X, 0)); |
| } |
| |
| [System.Obsolete] |
| public static int min(int[] X) { |
| return EnumerableExtensions.Min(EnumerableExtensions.DefaultIfEmpty(X, int.MaxValue)); |
| } |
| |
| [System.Obsolete] |
| public static int max(int[] X) { |
| return EnumerableExtensions.Max(EnumerableExtensions.DefaultIfEmpty(X, int.MinValue)); |
| } |
| |
| [System.Obsolete] |
| public static int sum(int[] X) { |
| return EnumerableExtensions.Sum(X); |
| } |
| #endif |
| |
| public static void WriteReport(string filename, string data) { |
| string absoluteFilename = GetAbsoluteFileName(filename); |
| |
| System.IO.Directory.CreateDirectory(System.IO.Path.GetDirectoryName(absoluteFilename)); |
| System.IO.File.AppendAllText(absoluteFilename, data); |
| } |
| |
| public static string GetAbsoluteFileName(string filename) { |
| string personalFolder = System.Environment.GetFolderPath(System.Environment.SpecialFolder.Personal); |
| return personalFolder + System.IO.Path.DirectorySeparatorChar + |
| ANTLRWORKS_DIR + System.IO.Path.DirectorySeparatorChar + |
| filename; |
| } |
| } |
| } |