1  #region License Information


2  /* HeuristicLab


3  * Copyright (C) Heuristic and Evolutionary Algorithms Laboratory (HEAL)


4  *


5  * This file is part of HeuristicLab.


6  *


7  * HeuristicLab is free software: you can redistribute it and/or modify


8  * it under the terms of the GNU General Public License as published by


9  * the Free Software Foundation, either version 3 of the License, or


10  * (at your option) any later version.


11  *


12  * HeuristicLab is distributed in the hope that it will be useful,


13  * but WITHOUT ANY WARRANTY; without even the implied warranty of


14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the


15  * GNU General Public License for more details.


16  *


17  * You should have received a copy of the GNU General Public License


18  * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.


19  */


20  #endregion


21 


22  using System;


23  namespace HeuristicLab.Common {


24  public static class DoubleExtensions {


25  /// <summary>


26  /// Compares the similarity of value x and value y with a precision of 1.0E12.


27  /// </summary>


28  /// <param name="x">First double value to be checked</param>


29  /// <param name="y">Second double value to compare with</param>


30  /// <returns>true if the difference is <= 1.0E12</returns>


31  public static bool IsAlmost(this double x, double y) {


32  var epsilon = 1.0E12;


33  return IsAlmost(x, y, epsilon);


34  }


35 


36  /// <summary>


37  /// Compares the similarity of value x and value y with a given precision (epsilon).


38  /// </summary>


39  /// <param name="x">First double value to be checked</param>


40  /// <param name="y">Second double value to compare with</param>


41  /// <param name="epsilon">Error term to specify the precision</param>


42  /// <returns>true if the difference is <= epsilon</returns>


43  public static bool IsAlmost(this double x, double y, double epsilon) {


44  if (double.IsInfinity(x)) {


45  if (x > 0) return double.IsPositiveInfinity(y);


46  else return double.IsNegativeInfinity(y);


47  } else {


48  return Math.Abs(x  y) < epsilon;


49  }


50  }


51  }


52  }

