Improve warning message in ElasticNet (#8565)

Sentient07 · lesteve · commit eba8a6a66c7c · 2017-03-17T11:05:17.000+01:00
diff --git a/sklearn/linear_model/cd_fast.pyx b/sklearn/linear_model/cd_fast.pyx
@@ -217,8 +217,8 @@ def enet_coordinate_descent(np.ndarray[floating, ndim=1] w,
     cdef floating *R_data = <floating*> R.data
     cdef floating *XtA_data = <floating*> XtA.data
 
-    if alpha == 0:
-        warnings.warn("Coordinate descent with alpha=0 may lead to unexpected"
+    if alpha == 0 and beta == 0:
+        warnings.warn("Coordinate descent with no regularization may lead to unexpected"
             " results and is discouraged.")
 
     with nogil:
