From ad70668bc66f9d82c8a62b07dec184e5db335558 Mon Sep 17 00:00:00 2001
From: Stefan van der Walt <stefan@sun.ac.za>
Date: Mon, 29 Sep 2014 01:21:24 +0200
Subject: [PATCH] Document output of polygon_area

---
 skimage/_shared/_geometry.py | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/skimage/_shared/_geometry.py b/skimage/_shared/_geometry.py
index 27a03eef..6406b56d 100644
--- a/skimage/_shared/_geometry.py
+++ b/skimage/_shared/_geometry.py
@@ -42,6 +42,11 @@ def polygon_area(py, px):
     ----------
     py, px : (N,) array of float
         Polygon coordinates.
+
+    Returns
+    -------
+    a : float
+        Area of the polygon.
     """
     py = np.asarray(py)
     px = np.asarray(px)