From fb8c8d02663c2a19565e3d156127220fd552f4dc Mon Sep 17 00:00:00 2001
From: Thomas FORGIONE <thomas.forgione@gmail.com>
Date: Wed, 18 Jan 2017 14:42:51 +0100
Subject: [PATCH] Update geometry

---
 d3/geometry.py | 41 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 41 insertions(+)

diff --git a/d3/geometry.py b/d3/geometry.py
index fbbdd81..276250d 100644
--- a/d3/geometry.py
+++ b/d3/geometry.py
@@ -1,33 +1,62 @@
 import math
 
 class Vector:
+    """ 3D Vector
+
+    Simple class that represents a 3D vector
+    """
+
     def __init__(self, x = 0.0, y = 0.0, z = 0.0):
+        """
+        Creates a vector from it's coordinates
+        """
         self.x = x
         self.y = y
         self.z = z
 
     def from_array(self, arr):
+        """
+        Creates a vector from an array
+        """
         self.x = float(arr[0]) if len(arr) > 0 else None
         self.y = float(arr[1]) if len(arr) > 1 else None
         self.z = float(arr[2]) if len(arr) > 2 else None
         return self
 
     def __add__(self, other):
+        """
+        Sums two vectors
+        """
         return Vector(self.x + other.x, self.y + other.y, self.z + other.z)
 
     def __mul__(self, other):
+        """
+        Computes the product between a vector and a number
+        """
         return Vector(self.x * other, self.y * other, self.z * other)
 
     def __rmul__(self, other):
+        """
+        Computes the product between a vector and a number
+        """
         return self.__mul__(other)
 
     def norm2(self):
+        """
+        Computes the square of the norm of a vector
+        """
         return self.x * self.x + self.y * self.y + self.z * self.z
 
     def norm(self):
+        """
+        Compute the norm of a vector
+        """
         return math.sqrt(self.norm2())
 
     def normalize(self):
+        """
+        Divides each coordinate of the vector by its norm
+        """
         norm = self.norm()
         if abs(norm) > 0.0001:
             self.x /= norm
@@ -35,21 +64,33 @@ class Vector:
             self.z /= norm
 
     def cross_product(v1, v2):
+        """
+        Computes the cross product between the two vectors
+        """
         return Vector(
             v1.y * v2.z - v1.z * v2.y,
             v1.z * v2.x - v1.x * v2.z,
             v1.x * v2.y - v1.y * v2.x)
 
     def from_points(v1, v2):
+        """
+        Creates a vector from two points
+        """
         return Vector(
             v2.x - v1.x,
             v2.y - v1.y,
             v2.z - v1.z)
 
     def __str__(self):
+        """
+        Prints the coordinates of the vector between partheses
+        """
         return '(' + ", ".join([str(self.x), str(self.y), str(self.z)]) + ")"
 
     def dot(self, other):
+        """
+        Computes the dot product of two vectors
+        """
         return self.x * other.x + self.y * other.y + self.z * other.z