Merge pull request #4852 from jreback/seq2

BUG: (GH4851) path for 0-dim arrays in DataFrame construction were incorrect

Author: jreback

doc/source/release.rst

@@ -114,7 +114,7 @@ Improvements to existing features
   - ``Panel.to_excel()`` now accepts keyword arguments that will be passed to
     its ``DataFrame``'s ``to_excel()`` methods. (:issue:`4750`)
   - allow DataFrame constructor to accept more list-like objects, e.g. list of
-    ``collections.Sequence`` and ``array.Array`` objects (:issue:`3783`,:issue:`42971`),
+    ``collections.Sequence`` and ``array.Array`` objects (:issue:`3783`,:issue:`4297`, :issue:`4851`),
     thanks @lgautier
   - DataFrame constructor now accepts a numpy masked record array (:issue:`3478`),
     thanks @jnothman

pandas/core/frame.py

@@ -429,7 +429,7 @@ def __init__(self, data=None, index=None, columns=None, dtype=None,
                 if index is None and isinstance(data[0], Series):
                     index = _get_names_from_index(data)
 
-                if is_list_like(data[0]) and getattr(data[0],'ndim',0) <= 1:
+                if is_list_like(data[0]) and getattr(data[0],'ndim',1) == 1:
                     arrays, columns = _to_arrays(data, columns, dtype=dtype)
                     columns = _ensure_index(columns)
 
@@ -4710,7 +4710,7 @@ def extract_index(data):
             elif isinstance(v, dict):
                 have_dicts = True
                 indexes.append(list(v.keys()))
-            elif is_list_like(v) and getattr(v,'ndim',0) <= 1:
+            elif is_list_like(v) and getattr(v,'ndim',1) == 1:
                 have_raw_arrays = True
                 raw_lengths.append(len(v))
 

pandas/tests/test_frame.py

@@ -2675,6 +2675,13 @@ def test_constructor_list_of_lists(self):
         self.assert_(com.is_integer_dtype(df['num']))
         self.assert_(df['str'].dtype == np.object_)
 
+        # GH 4851
+        # list of 0-dim ndarrays
+        expected = DataFrame({ 0: range(10) })
+        data = [np.array(x) for x in range(10)]
+        result = DataFrame(data)
+        assert_frame_equal(result, expected)
+
     def test_constructor_sequence_like(self):
         # GH 3783
         # collections.Squence like