Resolves #3467 (#3429)

Co-authored-by: Amanda Potts <ajpotts@users.noreply.github.com>

PROTO_tests/tests/dataframe_test.py

@@ -11,6 +11,7 @@
 import arkouda as ak
 from arkouda import io_util
 from arkouda.scipy import chisquare as akchisquare
+from arkouda.testing import assert_frame_equal as ak_assert_frame_equal
 
 
 def alternating_1_0(n):
@@ -239,6 +240,46 @@ def test_dataframe_creation(self, size):
         ak_to_pd = akdf.to_pandas()
         assert_frame_equal(pddf, ak_to_pd)
 
+    @pytest.mark.parametrize("size", pytest.prob_size)
+    @pytest.mark.parametrize("dtype", ["float64", "int64"])
+    def test_from_pandas_with_index(self, size, dtype):
+        np_arry = np.arange(size, dtype=dtype)
+        np_arry = np_arry[::2] * -1.0  # Alter so that index is different from default
+        idx = pd.Index(np_arry)
+        pd_df = pd.DataFrame({"col1": np_arry}, index=idx)
+        ak_df = ak.DataFrame(pd_df)
+        assert pd_df.index.inferred_type == ak_df.index.inferred_type
+
+        ak_arry = ak.arange(size, dtype=dtype)
+        ak_arry = ak_arry[::2] * -1.0
+        idx = ak.Index(ak_arry)
+        expected_df = ak.DataFrame({"col1": ak_arry}, index=idx)
+
+        ak_assert_frame_equal(ak_df, expected_df)
+
+    @pytest.mark.parametrize("size", pytest.prob_size)
+    @pytest.mark.parametrize("dtype", ["float64", "int64"])
+    def test_round_trip_pandas_conversion(self, size, dtype):
+        a = ak.arange(size, dtype=dtype)
+        a = a[::2] * -1.0  # Alter so that index is different from default
+        idx = ak.Index(a)
+        original_df = ak.DataFrame({"col1": a}, index=idx)
+        round_trip_df = ak.DataFrame(original_df.to_pandas(retain_index=True))
+
+        ak_assert_frame_equal(original_df, round_trip_df)
+
+    @pytest.mark.parametrize("size", pytest.prob_size)
+    def test_round_trip_dataframe_conversion2(self, size):
+
+        a = ak.arange(size, dtype="float64") + 0.001
+
+        idx = ak.Index(a)
+        df = ak.DataFrame({"col1": a}, index=idx)
+        pd_df = df.to_pandas(retain_index=True)
+        round_trip_df = ak.DataFrame(pd_df)
+
+        ak.assert_frame_equal(df, round_trip_df)
+
     def test_convenience_init(self):
         dict1 = {"0": [1, 2], "1": [True, False], "2": ["foo", "bar"], "3": [2.3, -1.8]}
         dict2 = {"0": (1, 2), "1": (True, False), "2": ("foo", "bar"), "3": (2.3, -1.8)}

arkouda/dataframe.py

@@ -18,7 +18,6 @@
 from arkouda.client import generic_msg, maxTransferBytes
 from arkouda.client_dtypes import BitVector, Fields, IPv4
 from arkouda.dtypes import BigInt
-
 from arkouda.dtypes import bool_ as akbool
 from arkouda.dtypes import float64 as akfloat64
 from arkouda.dtypes import int64 as akint64
@@ -884,6 +883,7 @@ def __init__(self, initialdata=None, index=None, columns=None):
             self.data = initialdata.data
             self.update_nrows()
             return
+
         elif isinstance(initialdata, pd.DataFrame):
             # copy pd.DataFrame data into the ak.DataFrame object
             self._nrows = initialdata.shape[0]
@@ -892,14 +892,15 @@ def __init__(self, initialdata=None, index=None, columns=None):
             self._columns = initialdata.columns.tolist()
 
             if index is None:
-                self._set_index(initialdata.index.values.tolist())
+                self._set_index(initialdata.index)
             else:
                 self._set_index(index)
             self.data = {}
             for key in initialdata.columns:
                 self.data[key] = (
                     SegArray.from_multi_array([array(r) for r in initialdata[key]])
-                    if isinstance(initialdata[key][0], (list, np.ndarray))
+                    if hasattr(initialdata[key], "values")
+                    and isinstance(initialdata[key].values[0], (list, np.ndarray))
                     else array(initialdata[key])
                 )
 
@@ -1849,7 +1850,7 @@ def index(self):
     def _set_index(self, value):
         if isinstance(value, Index) or value is None:
             self._index = value
-        elif isinstance(value, (pdarray, Strings)):
+        elif isinstance(value, (pdarray, Strings, pd.Index)):
             self._index = Index(value)
         elif isinstance(value, list):
             self._index = Index(array(value))