Add support for Slice to Matrix, SquareMatrix, Vector

matrix/Vector3.hpp

@@ -19,9 +19,12 @@ class Matrix;
 template <typename Type, size_t M>
 class Vector;
 
-template<typename Type>
+template <typename Type>
 class Dcm;
 
+template <typename Type>
+class Vector2;
+
 template<typename Type>
 class Vector3 : public Vector<Type, 3>
 {
@@ -48,6 +51,11 @@ public:
         v(2) = z;
     }
 
+    template<size_t P, size_t Q>
+    Vector3(const Slice<Type, 3, 1, P, Q>& slice_in) : Vector<Type, 3>(slice_in)
+    {
+    }
+
     Vector3 cross(const Matrix31 & b) const {
         const Vector3 &a(*this);
         Vector3 c;