init

Common/DTS.Common.Calculations/Integral.cs

@@ -0,0 +1,28 @@
+namespace DTS.Common.Calculations
+{
+    public static class Integral
+    {
+        /// <summary>
+        /// integrates a channel over an interval
+        /// </summary>
+        /// <param name="input">data to integrate</param>
+        /// <param name="start">index to start integration at (inclusive)</param>
+        /// <param name="end">index to end integration at (inclusive)</param>
+        /// <returns></returns>
+        public static double DefiniteIntegral(double[] input, int start, int end, double SPS)
+        {
+            //we use trapezoidal summation to get integral, there is an assumption that the input data is 
+            //tightly time aligned (otherwise we'd have to divide each interval by the actual distance, and not 1/2)
+            //=(SUMPRODUCT(H25:H56,A26:A57)-SUMPRODUCT(A25:A56,H26:H57)+A57*H57-A25*H25)/2
+            double d = 0;
+            for (int i = start + 1; i < end; i++)
+            {
+                d += 2D * input[i];
+            }
+            d += input[start];
+            d += input[end];
+
+            return .5D * d / SPS;
+        }
+    }
+}