Merge pull request #28 from weikang9009/constant

fix check_constant returns

Author: Ziqi-Li

spglm/glm.py

@@ -89,7 +89,7 @@ def __init__(self, y, X, family=family.Gaussian(), offset=None, y_fix=None,
         USER.check_y(y, self.n)
         self.y = y
         if constant:
-            self.X = USER.check_constant(X)
+            self.X,_,_ = USER.check_constant(X)
         else:
             self.X = X
         self.family = family