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DataPRO/FftSharp/Windows/Tukey.cs

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+using System;
+
+namespace FftSharp.Windows
+{
+    public class Tukey : Window, IWindow
+    {
+        private readonly double Alpha;
+
+        public override string Name => "Tukey";
+        public override string Description =>
+            "A Tukey window has a flat center and tapers at the edges according to a cosine function. " +
+            "The amount of taper is defined by alpha (with low values being less taper). " +
+            "Tukey windows are ideal for analyzing transient data since the amplitude of transient signal " +
+            "in the time domain is less likely to be altered compared to using Hanning or flat top.";
+
+        public Tukey()
+        {
+            Alpha = .5;
+        }
+
+        public Tukey(double alpha = .5)
+        {
+            Alpha = alpha;
+        }
+        protected override double windowValue(int index, int size)
+        {
+            double m = 2 * Math.PI / (Alpha * size);
+            int edgeSizePoints = (int)(size * Alpha / 2);
+            bool isEdge = (index < edgeSizePoints) || (index > size - edgeSizePoints);
+
+            return isEdge ? (1 - Math.Cos(index * m)) / 2 : 1;
+        }
+    }
+}