From 317eef33f8d8a0c9c8e291c4c123f39f543201f8 Mon Sep 17 00:00:00 2001
From: Alan Saul <alan.daniel.saul@gmail.com>
Date: Thu, 30 Apr 2015 17:58:08 +0100
Subject: [PATCH] fixing constant mapping gradients

---
 GPy/mappings/constant.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/GPy/mappings/constant.py b/GPy/mappings/constant.py
index dd3481c5..5e235a88 100644
--- a/GPy/mappings/constant.py
+++ b/GPy/mappings/constant.py
@@ -37,4 +37,4 @@ class Constant(Mapping):
         self.C.gradient = 0.
 
     def gradients_X(self, dL_dF, X):
-        return np.zeros_like(X)
+        return dL_dF.sum(0)