Add subNorm and subDistance to Vector.

bbiwarg/Utility/Vector.cs

@@ -104,9 +104,13 @@ namespace bbiwarg.Utility
             }
         }
         public T norm()
+        {
+            return subNorm(elements.Length);
+        }
+        public T subNorm(int subLength)
         {
             T result = (dynamic)0;
-            for (int i = 0; i < elements.Length; i++)
+            for (int i = 0; i < subLength; i++)
             {
                 result += (dynamic)elements[i] * elements[i];
             }
@@ -117,6 +121,11 @@ namespace bbiwarg.Utility
             return (vector - this).norm();
         }
 
+        public T subDistance(Vector<T> vector, int subLength) {
+            return (vector - this).subNorm(subLength);
+        }
+
+
         private static void checkLength(Vector<T> vector1, Vector<T> vector2)
         {
             if (vector1.length() != vector2.length())