Link from Day 5

accidentally opening a jupyter notebook in api/
caused apidoc to try to incorporate that into
the api docs.

.gitignore

@@ -4,3 +4,4 @@
 *.egg-info
 doc/_build/
 *.ipynb_checkpoints/
+fancymath.log

README.md

@@ -50,3 +50,6 @@ $ pip install -e .
   python -m line_profiler -rmt module_to_profile.py.lprof
   > python -m line_profiler -rmt module_to_profile.py.lprof
   ```
+
+# Day 5 Resources
+- [5 Worlds](https://www.joelonsoftware.com/2002/05/06/five-worlds/) from Joel Spolsky's blog.

doc/conf.py

@@ -17,7 +17,13 @@ release = '0.0.1'
 extensions = ["sphinx.ext.autodoc", "sphinx.ext.viewcode"]
 
 templates_path = ['_templates']
-exclude_patterns = ['_build', 'Thumbs.db', '.DS_Store', '.ipynb_checkpoints']
+exclude_patterns = [
+    '_build',
+    'Thumbs.db',
+    '.DS_Store',
+    '.ipynb_checkpoints',
+    'api/.ipynb_checkpoints'
+]
 
 
 

src/fancymath/vector.py

@@ -36,6 +36,14 @@ class Vector(object):
         z = self.z + other.z
         return self.__class__(x, y, z)
 
+    def __mul__(self, other):
+        if not isinstance(other, Vector):
+            return NotImplemented
+        x = self.y * other.z - self.z * other.y
+        y = self.z * other.x - self.x * other.z
+        z = self.x * other.y - self.y * other.x
+        return self.__class__(x, y, z)
+
 
 if __name__ == "__main__":
     v1 = Vector(3, 4, 0)

test/test_vector.py

@@ -4,13 +4,47 @@ from fancymath.vector import Vector
 
 
 class TestVector(unittest.TestCase):
+    def test_cross_product(self):
+        # Dictionary of (v1, v2): v3
+        values = {
+            (Vector(1, 2, 3), Vector(3, 2, 1)): Vector(-4, 8, -4),
+            (Vector(0, 0, 0), Vector(1, 2, 3)): Vector(0, 0, 0),
+            (Vector(1, 0, 0), Vector(1, 0, 0)): Vector(0, 0, 0),
+        }
+
+        for inputs, expected in values.items():
+            v1, v2 = inputs
+            with self.subTest(v1=v1, v2=v2):
+                v3 = v1 * v2
+
+                self.assertIsInstance(v3, Vector)
+                self.assertEqual(v3.x, expected.x)
+                self.assertEqual(v3.y, expected.y)
+                self.assertEqual(v3.z, expected.z)
+
+    def test_cross_product_failure(self):
+        v1 = Vector(1, 2, 3)
+        v2 = (3, 2, 1)
+
+        with self.assertRaises(TypeError):
+            v1 * v2
+
+
     def test_add_vector(self):
         v1 = Vector(1, 2, 3)
         v2 = Vector(-3, -2, -1)
         v3 = v1 + v2
         self.assertIsInstance(v3, Vector)
         self.assertEqual(v3.x, v1.x + v2.x)
-        
+
+    def test_abs(self):
+        v1 = Vector(0, 0, 0)
+        v2 = Vector(1, 2, 2)
+        v3 = Vector(1, -2, 2)
+        self.assertEqual(v1.abs(), 0)
+        self.assertEqual(v2.abs(), 3)
+        self.assertEqual(v2.abs(), v3.abs())
+
     def test_dot_failure(self):
         with self.assertRaises(ValueError):
             v1 = Vector(1, 2, 3)