From 5b78b2a69e1616893a5c48472cc471638ba72d0e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Johannes=20Sch=C3=B6nberger?= <jschoenberger@demuc.de>
Date: Wed, 1 May 2013 12:26:04 +0200
Subject: [PATCH] Add is_degenerate to geometric transforms

---
 skimage/transform/_geometric.py | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/skimage/transform/_geometric.py b/skimage/transform/_geometric.py
index 448829de..4b2a38d5 100644
--- a/skimage/transform/_geometric.py
+++ b/skimage/transform/_geometric.py
@@ -41,6 +41,26 @@ class GeometricTransform(object):
         """
         raise NotImplementedError()
 
+    @classmethod
+    def is_degenerate(cls, data):
+        """Check whether set of points is degenerate.
+
+        Parameters
+        ----------
+        data : (N, 2) array
+            N points with `(x, y)` coordinates, respectively.
+
+        Returns
+        -------
+        flag : bool
+            Flag indicating if data is degenerate.
+
+        """
+
+        # by default never degenerate since system equations can be under-,
+        # well- and over-determined.
+        return False
+
     def __add__(self, other):
         """Combine this transformation with another.