done

lib/python3.11/site-packages/pandas/tests/frame/test_cumulative.py

@@ -0,0 +1,81 @@
+"""
+Tests for DataFrame cumulative operations
+
+See also
+--------
+tests.series.test_cumulative
+"""
+
+import numpy as np
+import pytest
+
+from pandas import (
+    DataFrame,
+    Series,
+)
+import pandas._testing as tm
+
+
+class TestDataFrameCumulativeOps:
+    # ---------------------------------------------------------------------
+    # Cumulative Operations - cumsum, cummax, ...
+
+    def test_cumulative_ops_smoke(self):
+        # it works
+        df = DataFrame({"A": np.arange(20)}, index=np.arange(20))
+        df.cummax()
+        df.cummin()
+        df.cumsum()
+
+        dm = DataFrame(np.arange(20).reshape(4, 5), index=range(4), columns=range(5))
+        # TODO(wesm): do something with this?
+        dm.cumsum()
+
+    def test_cumprod_smoke(self, datetime_frame):
+        datetime_frame.iloc[5:10, 0] = np.nan
+        datetime_frame.iloc[10:15, 1] = np.nan
+        datetime_frame.iloc[15:, 2] = np.nan
+
+        # ints
+        df = datetime_frame.fillna(0).astype(int)
+        df.cumprod(0)
+        df.cumprod(1)
+
+        # ints32
+        df = datetime_frame.fillna(0).astype(np.int32)
+        df.cumprod(0)
+        df.cumprod(1)
+
+    @pytest.mark.parametrize("method", ["cumsum", "cumprod", "cummin", "cummax"])
+    def test_cumulative_ops_match_series_apply(self, datetime_frame, method):
+        datetime_frame.iloc[5:10, 0] = np.nan
+        datetime_frame.iloc[10:15, 1] = np.nan
+        datetime_frame.iloc[15:, 2] = np.nan
+
+        # axis = 0
+        result = getattr(datetime_frame, method)()
+        expected = datetime_frame.apply(getattr(Series, method))
+        tm.assert_frame_equal(result, expected)
+
+        # axis = 1
+        result = getattr(datetime_frame, method)(axis=1)
+        expected = datetime_frame.apply(getattr(Series, method), axis=1)
+        tm.assert_frame_equal(result, expected)
+
+        # fix issue TODO: GH ref?
+        assert np.shape(result) == np.shape(datetime_frame)
+
+    def test_cumsum_preserve_dtypes(self):
+        # GH#19296 dont incorrectly upcast to object
+        df = DataFrame({"A": [1, 2, 3], "B": [1, 2, 3.0], "C": [True, False, False]})
+
+        result = df.cumsum()
+
+        expected = DataFrame(
+            {
+                "A": Series([1, 3, 6], dtype=np.int64),
+                "B": Series([1, 3, 6], dtype=np.float64),
+                "C": df["C"].cumsum(),
+            }
+        )
+        tm.assert_frame_equal(result, expected)