BUG: SparseDataFrame.icol return SparseSeries. SparseSeries.from_array return SparseSeries. close #2227, #2229

Author: wesm

RELEASE.rst

@@ -105,6 +105,7 @@ pandas 0.9.1
   - Fix SparseSeries.__pow__ issue with NA input (#2220)
   - Fix icol with integer sequence failure (#2228)
   - Fixed resampling tz-aware time series issue (#2245)
+  - SparseDataFrame.icol was not returning SparseSeries (#2227, #2229)
 
 pandas 0.9.0
 ============

pandas/core/frame.py

@@ -321,6 +321,7 @@ class DataFrame(NDFrame):
     _auto_consolidate = True
     _verbose_info = True
     _het_axis = 1
+    _col_klass = Series
 
     _AXIS_NUMBERS = {
         'index': 0,
@@ -1733,7 +1734,8 @@ def icol(self, i):
                     return self.ix[:, i]
 
             values = self._data.iget(i)
-            return Series.from_array(values, index=self.index, name=label)
+            return self._col_klass.from_array(values, index=self.index,
+                                              name=label)
 
     def _ixs(self, i, axis=0):
         if axis == 0:

pandas/sparse/frame.py

@@ -64,6 +64,7 @@ class SparseDataFrame(DataFrame):
     _columns = None
     _series = None
     _is_mixed_type = False
+    _col_klass = SparseSeries
     ndim = 2
 
     def __init__(self, data=None, index=None, columns=None,

pandas/sparse/series.py

@@ -146,6 +146,13 @@ def __new__(cls, data, index=None, sparse_index=None, kind='block',
         output.name = name
         return output
 
+    @classmethod
+    def from_array(cls, arr, index=None, name=None, copy=False):
+        """
+        Simplified alternate constructor
+        """
+        return SparseSeries(arr, index=index, name=name, copy=copy)
+
     def __init__(self, data, index=None, sparse_index=None, kind='block',
                  fill_value=None, name=None, copy=False):
         """Data structure for labeled, sparse floating point data

pandas/sparse/tests/test_sparse.py

@@ -901,6 +901,12 @@ def test_getitem(self):
 
         self.assertRaises(Exception, sdf.__getitem__, ['a', 'd'])
 
+    def test_icol(self):
+        # #2227
+        result = self.frame.icol(0)
+        self.assertTrue(isinstance(result, SparseSeries))
+        assert_sp_series_equal(result, self.frame['A'])
+
     def test_set_value(self):
         res = self.frame.set_value('foobar', 'B', 1.5)
         self.assert_(res is not self.frame)