Merge pull request #482 from AkashKarnatak/master

Fixed "get_arc_center()" method of Arc class

Author: leotrs

manim/mobject/geometry.py

@@ -288,6 +288,12 @@ def get_arc_center(self, warning=True):
         """
         # First two anchors and handles
         a1, h1, h2, a2 = self.points[:4]
+
+        if np.all(a1 == a2):
+            # For a1 and a2 to lie at the same point arc radius
+            # must be zero. Thus arc_center will also lie at
+            # that point.
+            return a1
         # Tangent vectors
         t1 = h1 - a1
         t2 = h2 - a2

tests/test_unit_geometry.py

@@ -0,0 +1,7 @@
+import pytest
+import numpy as np
+from manim import Sector
+
+
+def test_get_arc_center():
+    assert np.all(Sector(arc_center=[1, 2, 0]).get_arc_center() == [1, 2, 0])