Changeset 11313

Timestamp:

08/27/14 12:00:56 (10 years ago)

Author:

bburlacu

Message:

#2236: Added an overload of the GenerateSteps method accepting a Func<double,double> transform. Added GenerateLogarithmicSteps method for filling an interval with logarithmically spaced points.

File:

• trunk/sources/HeuristicLab.Problems.Instances.DataAnalysis/3.3/Regression/ValueGenerator.cs (modified) (1 diff)

trunk/sources/HeuristicLab.Problems.Instances.DataAnalysis/3.3/Regression/ValueGenerator.cs

@@ -46 +46 @@
         x += stepWidth;
       }
+    }
+
+    /// <summary>
+    /// Generate a logarithmic sequence between start and end by applying a power-of-10 function to an underlying evenly spaced sequence
+    /// </summary>
+    /// <param name="start">The start of the sequence</param>
+    /// <param name="end">The end of the sequence</param>
+    /// <param name="stepWidth">The stepwidth for the original sequence before the points are transformed</param>
+    /// <returns>A logarithmic sequence from start to end (inclusive)</returns>
+    public static IEnumerable<double> GenerateLogarithmicSteps(double start, double end, double stepWidth) {
+      return GenerateSteps(start, end, stepWidth, x => Math.Pow(10, x));
+    }
+
+    /// <summary>
+    /// Generates a sequence of points between start and end according to given transformation
+    /// </summary>
+    /// <param name="start">The smallest and first value of the sequence.</param>
+    /// <param name="end">The largest and last value of the sequence.</param>
+    /// <param name="stepWidth">The step size between subsequent values (before transform)</param>
+    /// <param name="transform">The transform function</param>
+    /// <returns></returns>
+    public static IEnumerable<double> GenerateSteps(double start, double end, double stepWidth, Func<double, double> transform) {
+      return GenerateSteps(start, end, stepWidth).Select(transform).Where(x => x < end || x.IsAlmost(end));
     }