334 lines
		
	
	
		
			9.3 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
			
		
		
	
	
			334 lines
		
	
	
		
			9.3 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
| # Test GroupBy._positional_selector positional grouped indexing GH#42864
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| 
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| import numpy as np
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| import pytest
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| 
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| import pandas as pd
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| import pandas._testing as tm
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| 
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| 
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| @pytest.mark.parametrize(
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|     "arg, expected_rows",
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|     [
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|         [0, [0, 1, 4]],
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|         [2, [5]],
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|         [5, []],
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|         [-1, [3, 4, 7]],
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|         [-2, [1, 6]],
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|         [-6, []],
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|     ],
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| )
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| def test_int(slice_test_df, slice_test_grouped, arg, expected_rows):
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|     # Test single integer
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|     result = slice_test_grouped._positional_selector[arg]
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|     expected = slice_test_df.iloc[expected_rows]
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| 
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|     tm.assert_frame_equal(result, expected)
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| 
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| 
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| def test_slice(slice_test_df, slice_test_grouped):
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|     # Test single slice
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|     result = slice_test_grouped._positional_selector[0:3:2]
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|     expected = slice_test_df.iloc[[0, 1, 4, 5]]
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| 
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|     tm.assert_frame_equal(result, expected)
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| 
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| 
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| @pytest.mark.parametrize(
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|     "arg, expected_rows",
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|     [
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|         [[0, 2], [0, 1, 4, 5]],
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|         [[0, 2, -1], [0, 1, 3, 4, 5, 7]],
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|         [range(0, 3, 2), [0, 1, 4, 5]],
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|         [{0, 2}, [0, 1, 4, 5]],
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|     ],
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|     ids=[
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|         "list",
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|         "negative",
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|         "range",
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|         "set",
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|     ],
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| )
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| def test_list(slice_test_df, slice_test_grouped, arg, expected_rows):
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|     # Test lists of integers and integer valued iterables
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|     result = slice_test_grouped._positional_selector[arg]
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|     expected = slice_test_df.iloc[expected_rows]
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| 
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|     tm.assert_frame_equal(result, expected)
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| 
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| 
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| def test_ints(slice_test_df, slice_test_grouped):
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|     # Test tuple of ints
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|     result = slice_test_grouped._positional_selector[0, 2, -1]
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|     expected = slice_test_df.iloc[[0, 1, 3, 4, 5, 7]]
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| 
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|     tm.assert_frame_equal(result, expected)
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| 
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| 
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| def test_slices(slice_test_df, slice_test_grouped):
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|     # Test tuple of slices
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|     result = slice_test_grouped._positional_selector[:2, -2:]
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|     expected = slice_test_df.iloc[[0, 1, 2, 3, 4, 6, 7]]
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| 
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|     tm.assert_frame_equal(result, expected)
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| 
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| 
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| def test_mix(slice_test_df, slice_test_grouped):
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|     # Test mixed tuple of ints and slices
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|     result = slice_test_grouped._positional_selector[0, 1, -2:]
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|     expected = slice_test_df.iloc[[0, 1, 2, 3, 4, 6, 7]]
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| 
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|     tm.assert_frame_equal(result, expected)
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| 
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| 
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| @pytest.mark.parametrize(
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|     "arg, expected_rows",
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|     [
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|         [0, [0, 1, 4]],
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|         [[0, 2, -1], [0, 1, 3, 4, 5, 7]],
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|         [(slice(None, 2), slice(-2, None)), [0, 1, 2, 3, 4, 6, 7]],
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|     ],
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| )
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| def test_as_index(slice_test_df, arg, expected_rows):
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|     # Test the default as_index behaviour
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|     result = slice_test_df.groupby("Group", sort=False)._positional_selector[arg]
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|     expected = slice_test_df.iloc[expected_rows]
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| 
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|     tm.assert_frame_equal(result, expected)
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| 
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| 
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| def test_doc_examples():
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|     # Test the examples in the documentation
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|     df = pd.DataFrame(
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|         [["a", 1], ["a", 2], ["a", 3], ["b", 4], ["b", 5]], columns=["A", "B"]
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|     )
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| 
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|     grouped = df.groupby("A", as_index=False)
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| 
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|     result = grouped._positional_selector[1:2]
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|     expected = pd.DataFrame([["a", 2], ["b", 5]], columns=["A", "B"], index=[1, 4])
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| 
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|     tm.assert_frame_equal(result, expected)
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| 
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|     result = grouped._positional_selector[1, -1]
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|     expected = pd.DataFrame(
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|         [["a", 2], ["a", 3], ["b", 5]], columns=["A", "B"], index=[1, 2, 4]
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|     )
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| 
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|     tm.assert_frame_equal(result, expected)
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| 
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| 
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| @pytest.fixture()
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| def multiindex_data():
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|     rng = np.random.default_rng(2)
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|     ndates = 100
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|     nitems = 20
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|     dates = pd.date_range("20130101", periods=ndates, freq="D")
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|     items = [f"item {i}" for i in range(nitems)]
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| 
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|     data = {}
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|     for date in dates:
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|         nitems_for_date = nitems - rng.integers(0, 12)
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|         levels = [
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|             (item, rng.integers(0, 10000) / 100, rng.integers(0, 10000) / 100)
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|             for item in items[:nitems_for_date]
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|         ]
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|         levels.sort(key=lambda x: x[1])
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|         data[date] = levels
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| 
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|     return data
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| 
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| 
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| def _make_df_from_data(data):
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|     rows = {}
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|     for date in data:
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|         for level in data[date]:
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|             rows[(date, level[0])] = {"A": level[1], "B": level[2]}
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| 
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|     df = pd.DataFrame.from_dict(rows, orient="index")
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|     df.index.names = ("Date", "Item")
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|     return df
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| 
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| 
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| def test_multiindex(multiindex_data):
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|     # Test the multiindex mentioned as the use-case in the documentation
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|     df = _make_df_from_data(multiindex_data)
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|     result = df.groupby("Date", as_index=False).nth(slice(3, -3))
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| 
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|     sliced = {date: multiindex_data[date][3:-3] for date in multiindex_data}
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|     expected = _make_df_from_data(sliced)
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| 
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|     tm.assert_frame_equal(result, expected)
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| 
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| 
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| @pytest.mark.parametrize("arg", [1, 5, 30, 1000, -1, -5, -30, -1000])
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| @pytest.mark.parametrize("method", ["head", "tail"])
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| @pytest.mark.parametrize("simulated", [True, False])
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| def test_against_head_and_tail(arg, method, simulated):
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|     # Test gives the same results as grouped head and tail
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|     n_groups = 100
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|     n_rows_per_group = 30
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| 
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|     data = {
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|         "group": [
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|             f"group {g}" for j in range(n_rows_per_group) for g in range(n_groups)
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|         ],
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|         "value": [
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|             f"group {g} row {j}"
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|             for j in range(n_rows_per_group)
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|             for g in range(n_groups)
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|         ],
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|     }
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|     df = pd.DataFrame(data)
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|     grouped = df.groupby("group", as_index=False)
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|     size = arg if arg >= 0 else n_rows_per_group + arg
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| 
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|     if method == "head":
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|         result = grouped._positional_selector[:arg]
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| 
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|         if simulated:
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|             indices = [
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|                 j * n_groups + i
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|                 for j in range(size)
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|                 for i in range(n_groups)
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|                 if j * n_groups + i < n_groups * n_rows_per_group
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|             ]
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|             expected = df.iloc[indices]
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| 
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|         else:
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|             expected = grouped.head(arg)
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| 
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|     else:
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|         result = grouped._positional_selector[-arg:]
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| 
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|         if simulated:
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|             indices = [
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|                 (n_rows_per_group + j - size) * n_groups + i
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|                 for j in range(size)
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|                 for i in range(n_groups)
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|                 if (n_rows_per_group + j - size) * n_groups + i >= 0
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|             ]
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|             expected = df.iloc[indices]
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| 
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|         else:
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|             expected = grouped.tail(arg)
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| 
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|     tm.assert_frame_equal(result, expected)
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| 
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| 
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| @pytest.mark.parametrize("start", [None, 0, 1, 10, -1, -10])
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| @pytest.mark.parametrize("stop", [None, 0, 1, 10, -1, -10])
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| @pytest.mark.parametrize("step", [None, 1, 5])
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| def test_against_df_iloc(start, stop, step):
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|     # Test that a single group gives the same results as DataFrame.iloc
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|     n_rows = 30
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| 
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|     data = {
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|         "group": ["group 0"] * n_rows,
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|         "value": list(range(n_rows)),
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|     }
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|     df = pd.DataFrame(data)
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|     grouped = df.groupby("group", as_index=False)
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| 
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|     result = grouped._positional_selector[start:stop:step]
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|     expected = df.iloc[start:stop:step]
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| 
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|     tm.assert_frame_equal(result, expected)
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| 
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| 
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| def test_series():
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|     # Test grouped Series
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|     ser = pd.Series([1, 2, 3, 4, 5], index=["a", "a", "a", "b", "b"])
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|     grouped = ser.groupby(level=0)
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|     result = grouped._positional_selector[1:2]
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|     expected = pd.Series([2, 5], index=["a", "b"])
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| 
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|     tm.assert_series_equal(result, expected)
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| 
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| 
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| @pytest.mark.parametrize("step", [1, 2, 3, 4, 5])
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| def test_step(step):
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|     # Test slice with various step values
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|     data = [["x", f"x{i}"] for i in range(5)]
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|     data += [["y", f"y{i}"] for i in range(4)]
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|     data += [["z", f"z{i}"] for i in range(3)]
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|     df = pd.DataFrame(data, columns=["A", "B"])
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| 
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|     grouped = df.groupby("A", as_index=False)
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| 
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|     result = grouped._positional_selector[::step]
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| 
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|     data = [["x", f"x{i}"] for i in range(0, 5, step)]
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|     data += [["y", f"y{i}"] for i in range(0, 4, step)]
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|     data += [["z", f"z{i}"] for i in range(0, 3, step)]
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| 
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|     index = [0 + i for i in range(0, 5, step)]
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|     index += [5 + i for i in range(0, 4, step)]
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|     index += [9 + i for i in range(0, 3, step)]
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| 
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|     expected = pd.DataFrame(data, columns=["A", "B"], index=index)
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| 
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|     tm.assert_frame_equal(result, expected)
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| 
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| 
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| @pytest.fixture()
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| def column_group_df():
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|     return pd.DataFrame(
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|         [[0, 1, 2, 3, 4, 5, 6], [0, 0, 1, 0, 1, 0, 2]],
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|         columns=["A", "B", "C", "D", "E", "F", "G"],
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|     )
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| 
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| 
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| def test_column_axis(column_group_df):
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|     msg = "DataFrame.groupby with axis=1"
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|     with tm.assert_produces_warning(FutureWarning, match=msg):
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|         g = column_group_df.groupby(column_group_df.iloc[1], axis=1)
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|     result = g._positional_selector[1:-1]
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|     expected = column_group_df.iloc[:, [1, 3]]
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| 
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|     tm.assert_frame_equal(result, expected)
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| 
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| 
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| def test_columns_on_iter():
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|     # GitHub issue #44821
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|     df = pd.DataFrame({k: range(10) for k in "ABC"})
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| 
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|     # Group-by and select columns
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|     cols = ["A", "B"]
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|     for _, dg in df.groupby(df.A < 4)[cols]:
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|         tm.assert_index_equal(dg.columns, pd.Index(cols))
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|         assert "C" not in dg.columns
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| 
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| 
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| @pytest.mark.parametrize("func", [list, pd.Index, pd.Series, np.array])
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| def test_groupby_duplicated_columns(func):
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|     # GH#44924
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|     df = pd.DataFrame(
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|         {
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|             "A": [1, 2],
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|             "B": [3, 3],
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|             "C": ["G", "G"],
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|         }
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|     )
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|     result = df.groupby("C")[func(["A", "B", "A"])].mean()
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|     expected = pd.DataFrame(
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|         [[1.5, 3.0, 1.5]], columns=["A", "B", "A"], index=pd.Index(["G"], name="C")
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|     )
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|     tm.assert_frame_equal(result, expected)
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| 
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| 
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| def test_groupby_get_nonexisting_groups():
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|     # GH#32492
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|     df = pd.DataFrame(
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|         data={
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|             "A": ["a1", "a2", None],
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|             "B": ["b1", "b2", "b1"],
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|             "val": [1, 2, 3],
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|         }
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|     )
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|     grps = df.groupby(by=["A", "B"])
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| 
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|     msg = "('a2', 'b1')"
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|     with pytest.raises(KeyError, match=msg):
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|         grps.get_group(("a2", "b1"))
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