Changeset 17301

Timestamp:

10/03/19 12:14:19 (3 years ago)

Author:

chaider

Message:

#3032 Fixed calculation problems for negative interval boundaries in cubic root

File:

• trunk/HeuristicLab.Problems.DataAnalysis/3.4/Implementation/Interval.cs (modified) (1 diff)

trunk/HeuristicLab.Problems.DataAnalysis/3.4/Implementation/Interval.cs

@@ -226 +226 @@
 
     public static Interval CubicRoot(Interval a) {
-      if (a.LowerBound < 0) return new Interval(double.NaN, double.NaN);
-      return new Interval(Math.Pow(a.LowerBound, 1.0/3), Math.Pow(a.UpperBound, 1.0/3));
+      var lower = (a.LowerBound < 0) ? -Math.Pow(-a.LowerBound, 1d / 3d) : Math.Pow(a.LowerBound, 1d / 3d);
+      var upper = (a.UpperBound < 0) ? -Math.Pow(-a.UpperBound, 1d / 3d) : Math.Pow(a.UpperBound, 1d / 3d);
+
+      return new Interval(lower, upper);
     }
     #endregion