1 files changed, 35 insertions, 0 deletions
diff --git a/photon.py b/photon.py
new file mode 100644
index 0000000..3472c1e
--- /dev/null
+++ b/photon.py
@@ -0,0 +1,35 @@
+import time
+import numpy as np
+
+def uniform_sphere(size=None):
+    """
+    Generate random points isotropically distributed across the unit sphere.
+
+    Args:
+        - size: int, *optional*
+            Number of points to generate. If no size is specified, a single
+            point is returned.
+
+    source: Weisstein, Eric W. "Sphere Point Picking." Mathworld. 
+    """
+
+    t0 = time.time()
+
+    theta, u = np.random.uniform(0.0, 2*np.pi, size), \
+        np.random.uniform(-1.0, 1.0, size)
+
+    c = np.sqrt(1-u**2)
+
+    x = c*np.cos(theta)
+    y = c*np.sin(theta)
+    z = u
+
+    points = np.empty((x.size, 3))
+    points[:,0] = x
+    points[:,1] = y
+    points[:,2] = z
+
+    if size is None:
+        return points[0]
+    else:
+        return points