Perceptron (unfinished)

test/machine_learning/perceptron/PerceptronTest.java

@@ -37,4 +37,20 @@ class PerceptronTest
     {
         new Perceptron().learn(this.positives, this.negatives);
     }
+
+    @Test
+    void shouldClassifyCorrect2()
+    {
+        var positives = new ArrayList<>(List.of(
+                new Vector(List.of(0d, 1.8d)),
+                new Vector(List.of(2d, 0.6d)))
+        );
+
+        var negatives = new ArrayList<>(List.of(
+                new Vector(List.of(-1.2d, 1.4d)),
+                new Vector(List.of(0.4d, -1d)))
+        );
+
+        new Perceptron().learn(positives, negatives);
+    }
 }

test/machine_learning/perceptron/VectorTest.java

@@ -45,7 +45,7 @@ class VectorTest
     }
 
     @Test
-    void shouldReturnCorrectVectorWhenScalar()
+    void shouldReturnCorrectVectorWhenScalarMultiplying()
     {
         var v1 = new Vector(List.of(1d, 2d));
         var v2 = new Vector(List.of(3d, 4d));
@@ -55,4 +55,27 @@ class VectorTest
 
         assertEquals(expected, result);
     }
+
+    @Test
+    void shouldReturnCorrectVectorWhenEuclid()
+    {
+        var v1 = new Vector(List.of(1d, 2d));
+
+        var result = v1.euclid();
+        var expected = Math.sqrt(5);
+
+        assertEquals(expected, result);
+    }
+
+    @Test
+    void shouldReturnCorrectVectorWhenDividing()
+    {
+        var v1 = new Vector(List.of(1d, 2d));
+        var div = 2d;
+
+        var result = v1.divide(div);
+        var expected = new Vector(List.of(0.5d, 1d));
+
+        assertEquals(expected, result);
+    }
 }