TST: split up pandas/tests/test_resample.py (pandas-dev#23872)

Author: simonjayhawkins

pandas/tests/resample/__init__.py

@@ -0,0 +1,264 @@
+# pylint: disable=E1101
+
+from datetime import datetime, timedelta
+
+import numpy as np
+import pytest
+
+from pandas.compat import range, zip
+from pandas.errors import AbstractMethodError
+
+import pandas as pd
+from pandas import DataFrame, Series
+from pandas.core.groupby.groupby import DataError
+from pandas.core.indexes.datetimes import date_range
+from pandas.core.indexes.period import PeriodIndex, period_range
+from pandas.core.indexes.timedeltas import TimedeltaIndex
+from pandas.core.resample import TimeGrouper
+import pandas.util.testing as tm
+from pandas.util.testing import (
+    assert_almost_equal, assert_frame_equal, assert_index_equal,
+    assert_series_equal)
+
+from pandas.tseries.offsets import BDay
+
+business_day_offset = BDay()
+
+# The various methods we support
+downsample_methods = ['min', 'max', 'first', 'last', 'sum', 'mean', 'sem',
+                      'median', 'prod', 'var', 'ohlc', 'quantile']
+upsample_methods = ['count', 'size']
+series_methods = ['nunique']
+resample_methods = downsample_methods + upsample_methods + series_methods
+
+
+def simple_date_range_series(start, end, freq='D'):
+    """
+    Series with date range index and random data for test purposes.
+    """
+    rng = date_range(start, end, freq=freq)
+    return Series(np.random.randn(len(rng)), index=rng)
+
+
+def simple_period_range_series(start, end, freq='D'):
+    """
+    Series with period range index and random data for test purposes.
+    """
+    rng = period_range(start, end, freq=freq)
+    return Series(np.random.randn(len(rng)), index=rng)
+
+
+class Base(object):
+    """
+    base class for resampling testing, calling
+    .create_series() generates a series of each index type
+    """
+
+    def create_index(self, *args, **kwargs):
+        """ return the _index_factory created using the args, kwargs """
+        factory = self._index_factory()
+        return factory(*args, **kwargs)
+
+    @pytest.fixture
+    def _index_start(self):
+        return datetime(2005, 1, 1)
+
+    @pytest.fixture
+    def _index_end(self):
+        return datetime(2005, 1, 10)
+
+    @pytest.fixture
+    def _index_freq(self):
+        return 'D'
+
+    @pytest.fixture
+    def index(self, _index_start, _index_end, _index_freq):
+        return self.create_index(_index_start, _index_end, freq=_index_freq)
+
+    @pytest.fixture
+    def _series_name(self):
+        raise AbstractMethodError(self)
+
+    @pytest.fixture
+    def _static_values(self, index):
+        return np.arange(len(index))
+
+    @pytest.fixture
+    def series(self, index, _series_name, _static_values):
+        return Series(_static_values, index=index, name=_series_name)
+
+    @pytest.fixture
+    def frame(self, index, _static_values):
+        return DataFrame({'value': _static_values}, index=index)
+
+    @pytest.fixture(params=[Series, DataFrame])
+    def series_and_frame(self, request, index, _series_name, _static_values):
+        if request.param == Series:
+            return Series(_static_values, index=index, name=_series_name)
+        if request.param == DataFrame:
+            return DataFrame({'value': _static_values}, index=index)
+
+    @pytest.mark.parametrize('freq', ['2D', '1H'])
+    def test_asfreq(self, series_and_frame, freq):
+        obj = series_and_frame
+
+        result = obj.resample(freq).asfreq()
+        new_index = self.create_index(obj.index[0], obj.index[-1], freq=freq)
+        expected = obj.reindex(new_index)
+        assert_almost_equal(result, expected)
+
+    def test_asfreq_fill_value(self):
+        # test for fill value during resampling, issue 3715
+
+        s = self.create_series()
+
+        result = s.resample('1H').asfreq()
+        new_index = self.create_index(s.index[0], s.index[-1], freq='1H')
+        expected = s.reindex(new_index)
+        assert_series_equal(result, expected)
+
+        frame = s.to_frame('value')
+        frame.iloc[1] = None
+        result = frame.resample('1H').asfreq(fill_value=4.0)
+        new_index = self.create_index(frame.index[0],
+                                      frame.index[-1], freq='1H')
+        expected = frame.reindex(new_index, fill_value=4.0)
+        assert_frame_equal(result, expected)
+
+    def test_resample_interpolate(self):
+        # # 12925
+        df = self.create_series().to_frame('value')
+        assert_frame_equal(
+            df.resample('1T').asfreq().interpolate(),
+            df.resample('1T').interpolate())
+
+    def test_raises_on_non_datetimelike_index(self):
+        # this is a non datetimelike index
+        xp = DataFrame()
+        pytest.raises(TypeError, lambda: xp.resample('A').mean())
+
+    def test_resample_empty_series(self):
+        # GH12771 & GH12868
+
+        s = self.create_series()[:0]
+
+        for freq in ['M', 'D', 'H']:
+            # need to test for ohlc from GH13083
+            methods = [method for method in resample_methods
+                       if method != 'ohlc']
+            for method in methods:
+                result = getattr(s.resample(freq), method)()
+
+                expected = s.copy()
+                expected.index = s.index._shallow_copy(freq=freq)
+                assert_index_equal(result.index, expected.index)
+                assert result.index.freq == expected.index.freq
+                assert_series_equal(result, expected, check_dtype=False)
+
+    def test_resample_empty_dataframe(self):
+        # GH13212
+        index = self.create_series().index[:0]
+        f = DataFrame(index=index)
+
+        for freq in ['M', 'D', 'H']:
+            # count retains dimensions too
+            methods = downsample_methods + upsample_methods
+            for method in methods:
+                result = getattr(f.resample(freq), method)()
+                if method != 'size':
+                    expected = f.copy()
+                else:
+                    # GH14962
+                    expected = Series([])
+
+                expected.index = f.index._shallow_copy(freq=freq)
+                assert_index_equal(result.index, expected.index)
+                assert result.index.freq == expected.index.freq
+                assert_almost_equal(result, expected, check_dtype=False)
+
+            # test size for GH13212 (currently stays as df)
+
+    @pytest.mark.parametrize("index", tm.all_timeseries_index_generator(0))
+    @pytest.mark.parametrize(
+        "dtype",
+        [np.float, np.int, np.object, 'datetime64[ns]'])
+    def test_resample_empty_dtypes(self, index, dtype):
+
+        # Empty series were sometimes causing a segfault (for the functions
+        # with Cython bounds-checking disabled) or an IndexError.  We just run
+        # them to ensure they no longer do.  (GH #10228)
+        for how in downsample_methods + upsample_methods:
+            empty_series = Series([], index, dtype)
+            try:
+                getattr(empty_series.resample('d'), how)()
+            except DataError:
+                # Ignore these since some combinations are invalid
+                # (ex: doing mean with dtype of np.object)
+                pass
+
+    def test_resample_loffset_arg_type(self):
+        # GH 13218, 15002
+        df = self.create_series().to_frame('value')
+        expected_means = [df.values[i:i + 2].mean()
+                          for i in range(0, len(df.values), 2)]
+        expected_index = self.create_index(df.index[0],
+                                           periods=len(df.index) / 2,
+                                           freq='2D')
+
+        # loffset coerces PeriodIndex to DateTimeIndex
+        if isinstance(expected_index, PeriodIndex):
+            expected_index = expected_index.to_timestamp()
+
+        expected_index += timedelta(hours=2)
+        expected = DataFrame({'value': expected_means}, index=expected_index)
+
+        for arg in ['mean', {'value': 'mean'}, ['mean']]:
+
+            result_agg = df.resample('2D', loffset='2H').agg(arg)
+
+            with tm.assert_produces_warning(FutureWarning,
+                                            check_stacklevel=False):
+                result_how = df.resample('2D', how=arg, loffset='2H')
+
+            if isinstance(arg, list):
+                expected.columns = pd.MultiIndex.from_tuples([('value',
+                                                               'mean')])
+
+            # GH 13022, 7687 - TODO: fix resample w/ TimedeltaIndex
+            if isinstance(expected.index, TimedeltaIndex):
+                with pytest.raises(AssertionError):
+                    assert_frame_equal(result_agg, expected)
+                    assert_frame_equal(result_how, expected)
+            else:
+                assert_frame_equal(result_agg, expected)
+                assert_frame_equal(result_how, expected)
+
+    def test_apply_to_empty_series(self):
+        # GH 14313
+        series = self.create_series()[:0]
+
+        for freq in ['M', 'D', 'H']:
+            result = series.resample(freq).apply(lambda x: 1)
+            expected = series.resample(freq).apply(np.sum)
+
+            assert_series_equal(result, expected, check_dtype=False)
+
+    def test_resampler_is_iterable(self):
+        # GH 15314
+        series = self.create_series()
+        freq = 'H'
+        tg = TimeGrouper(freq, convention='start')
+        grouped = series.groupby(tg)
+        resampled = series.resample(freq)
+        for (rk, rv), (gk, gv) in zip(resampled, grouped):
+            assert rk == gk
+            assert_series_equal(rv, gv)
+
+    def test_resample_quantile(self):
+        # GH 15023
+        s = self.create_series()
+        q = 0.75
+        freq = 'H'
+        result = s.resample(freq).quantile(q)
+        expected = s.resample(freq).agg(lambda x: x.quantile(q))
+        tm.assert_series_equal(result, expected)