From 6b7ca78ad5e68836dce8a59d5a46c1bc92bc9337 Mon Sep 17 00:00:00 2001
From: Grant Sanderson <grant@3blue1brown.com>
Date: Wed, 29 Aug 2018 00:09:57 -0700
Subject: [PATCH] Make fall back value in normalize an optional thing

---
 utils/space_ops.py | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/utils/space_ops.py b/utils/space_ops.py
index 3b65b4cd..0bc6b744 100644
--- a/utils/space_ops.py
+++ b/utils/space_ops.py
@@ -100,12 +100,15 @@ def project_along_vector(point, vector):
     return np.dot(point, matrix.T)
 
 
-def normalize(vect):
+def normalize(vect, fall_back=None):
     norm = get_norm(vect)
     if norm > 0:
         return vect / norm
     else:
-        return np.zeros(len(vect))
+        if fall_back is not None:
+            return fall_back
+        else:
+            return np.zeros(len(vect))
 
 
 def cross(v1, v2):