add alpha koef meaning

Author: asm-jaime

MLTests/GradientLearnWithAlphaTests.cs

@@ -0,0 +1,44 @@
+using FluentAssertions;
+using NUnit.Framework;
+
+namespace MLTests
+{
+    public class GradientLearnWithAlphaTests
+    {
+        private double LearnWeightByGradientAlpha(double weight, double input, double predictionGoal, double alpha, int iterations)
+        {
+            var result = weight;
+            for (int iteration = 0; iteration < iterations; iteration++)
+            {
+                var prediction = input * result;
+                var error = Math.Pow(prediction - predictionGoal, 2);
+                var delta = prediction - predictionGoal;
+                var weightDelta = delta * input;
+                result = result - alpha * weightDelta;
+            }
+            return result;
+        }
+
+        private double FunctionLearnWeight(double weight, double input, double predictionGoal, double alpha, int iterations)
+        {
+            var result = weight;
+            for(int iteration = 0; iteration < iterations; iteration++)
+            {
+                var prediction = result * input;
+                var error = Math.Pow(prediction - predictionGoal, 2);
+                var derivative = (prediction - predictionGoal) * input;
+                result = result - alpha * derivative;
+            }
+            return result;
+        }
+
+        [Test]
+        public void ShouldNotBreakLearnWeight()
+        {
+            var (weight, input, predictionGoal, alpha, iterations) = (0.0, 2.0, 0.8, 0.1, 10);
+            var learnedWeight = FunctionLearnWeight(weight, input, predictionGoal, alpha, iterations);
+            var result = Math.Round(learnedWeight * input, 2);
+            result.Should().Be(0.8);
+        }
+    }
+}