diff --git a/environment_ci.yml b/environment_ci.yml
index 92ae60a..232d941 100644
--- a/environment_ci.yml
+++ b/environment_ci.yml
@@ -8,4 +8,4 @@ dependencies:
   - wheel==0.29.0
   - coverage==3.7.1
   - python-coveralls==2.5.0
-  - numpy==1.12.0
+  - numpy==1.15.4
diff --git a/xnumpy/core.py b/xnumpy/core.py
index 6146866..d98bac2 100644
--- a/xnumpy/core.py
+++ b/xnumpy/core.py
@@ -38,6 +38,9 @@ def expand(new_array,
                                                  tiling in various dimension.
 
         Examples:
+
+            >>> numpy.set_printoptions(legacy="1.13")
+
             >>> a = numpy.arange(6, dtype=numpy.uint64).reshape(2,3)
             >>> a
             array([[0, 1, 2],