import numpy as np import pytest from pandas._libs import lib, writers as libwriters from pandas import Index import pandas._testing as tm class TestMisc: def test_max_len_string_array(self): arr = a = np.array(["foo", "b", np.nan], dtype="object") assert libwriters.max_len_string_array(arr) == 3 # unicode arr = a.astype("U").astype(object) assert libwriters.max_len_string_array(arr) == 3 # bytes for python3 arr = a.astype("S").astype(object) assert libwriters.max_len_string_array(arr) == 3 # raises with pytest.raises(TypeError): libwriters.max_len_string_array(arr.astype("U")) def test_fast_unique_multiple_list_gen_sort(self): keys = [["p", "a"], ["n", "d"], ["a", "s"]] gen = (key for key in keys) expected = np.array(["a", "d", "n", "p", "s"]) out = lib.fast_unique_multiple_list_gen(gen, sort=True) tm.assert_numpy_array_equal(np.array(out), expected) gen = (key for key in keys) expected = np.array(["p", "a", "n", "d", "s"]) out = lib.fast_unique_multiple_list_gen(gen, sort=False) tm.assert_numpy_array_equal(np.array(out), expected) class TestIndexing: def test_maybe_indices_to_slice_left_edge(self): target = np.arange(100) # slice indices = np.array([], dtype=np.int64) maybe_slice = lib.maybe_indices_to_slice(indices, len(target)) assert isinstance(maybe_slice, slice) tm.assert_numpy_array_equal(target[indices], target[maybe_slice]) for end in [1, 2, 5, 20, 99]: for step in [1, 2, 4]: indices = np.arange(0, end, step, dtype=np.int64) maybe_slice = lib.maybe_indices_to_slice(indices, len(target)) assert isinstance(maybe_slice, slice) tm.assert_numpy_array_equal(target[indices], target[maybe_slice]) # reverse indices = indices[::-1] maybe_slice = lib.maybe_indices_to_slice(indices, len(target)) assert isinstance(maybe_slice, slice) tm.assert_numpy_array_equal(target[indices], target[maybe_slice]) # not slice for case in [[2, 1, 2, 0], [2, 2, 1, 0], [0, 1, 2, 1], [-2, 0, 2], [2, 0, -2]]: indices = np.array(case, dtype=np.int64) maybe_slice = lib.maybe_indices_to_slice(indices, len(target)) assert not isinstance(maybe_slice, slice) tm.assert_numpy_array_equal(maybe_slice, indices) tm.assert_numpy_array_equal(target[indices], target[maybe_slice]) def test_maybe_indices_to_slice_right_edge(self): target = np.arange(100) # slice for start in [0, 2, 5, 20, 97, 98]: for step in [1, 2, 4]: indices = np.arange(start, 99, step, dtype=np.int64) maybe_slice = lib.maybe_indices_to_slice(indices, len(target)) assert isinstance(maybe_slice, slice) tm.assert_numpy_array_equal(target[indices], target[maybe_slice]) # reverse indices = indices[::-1] maybe_slice = lib.maybe_indices_to_slice(indices, len(target)) assert isinstance(maybe_slice, slice) tm.assert_numpy_array_equal(target[indices], target[maybe_slice]) # not slice indices = np.array([97, 98, 99, 100], dtype=np.int64) maybe_slice = lib.maybe_indices_to_slice(indices, len(target)) assert not isinstance(maybe_slice, slice) tm.assert_numpy_array_equal(maybe_slice, indices) with pytest.raises(IndexError): target[indices] with pytest.raises(IndexError): target[maybe_slice] indices = np.array([100, 99, 98, 97], dtype=np.int64) maybe_slice = lib.maybe_indices_to_slice(indices, len(target)) assert not isinstance(maybe_slice, slice) tm.assert_numpy_array_equal(maybe_slice, indices) with pytest.raises(IndexError): target[indices] with pytest.raises(IndexError): target[maybe_slice] for case in [[99, 97, 99, 96], [99, 99, 98, 97], [98, 98, 97, 96]]: indices = np.array(case, dtype=np.int64) maybe_slice = lib.maybe_indices_to_slice(indices, len(target)) assert not isinstance(maybe_slice, slice) tm.assert_numpy_array_equal(maybe_slice, indices) tm.assert_numpy_array_equal(target[indices], target[maybe_slice]) def test_maybe_indices_to_slice_both_edges(self): target = np.arange(10) # slice for step in [1, 2, 4, 5, 8, 9]: indices = np.arange(0, 9, step, dtype=np.int64) maybe_slice = lib.maybe_indices_to_slice(indices, len(target)) assert isinstance(maybe_slice, slice) tm.assert_numpy_array_equal(target[indices], target[maybe_slice]) # reverse indices = indices[::-1] maybe_slice = lib.maybe_indices_to_slice(indices, len(target)) assert isinstance(maybe_slice, slice) tm.assert_numpy_array_equal(target[indices], target[maybe_slice]) # not slice for case in [[4, 2, 0, -2], [2, 2, 1, 0], [0, 1, 2, 1]]: indices = np.array(case, dtype=np.int64) maybe_slice = lib.maybe_indices_to_slice(indices, len(target)) assert not isinstance(maybe_slice, slice) tm.assert_numpy_array_equal(maybe_slice, indices) tm.assert_numpy_array_equal(target[indices], target[maybe_slice]) def test_maybe_indices_to_slice_middle(self): target = np.arange(100) # slice for start, end in [(2, 10), (5, 25), (65, 97)]: for step in [1, 2, 4, 20]: indices = np.arange(start, end, step, dtype=np.int64) maybe_slice = lib.maybe_indices_to_slice(indices, len(target)) assert isinstance(maybe_slice, slice) tm.assert_numpy_array_equal(target[indices], target[maybe_slice]) # reverse indices = indices[::-1] maybe_slice = lib.maybe_indices_to_slice(indices, len(target)) assert isinstance(maybe_slice, slice) tm.assert_numpy_array_equal(target[indices], target[maybe_slice]) # not slice for case in [[14, 12, 10, 12], [12, 12, 11, 10], [10, 11, 12, 11]]: indices = np.array(case, dtype=np.int64) maybe_slice = lib.maybe_indices_to_slice(indices, len(target)) assert not isinstance(maybe_slice, slice) tm.assert_numpy_array_equal(maybe_slice, indices) tm.assert_numpy_array_equal(target[indices], target[maybe_slice]) def test_maybe_booleans_to_slice(self): arr = np.array([0, 0, 1, 1, 1, 0, 1], dtype=np.uint8) result = lib.maybe_booleans_to_slice(arr) assert result.dtype == np.bool_ result = lib.maybe_booleans_to_slice(arr[:0]) assert result == slice(0, 0) def test_get_reverse_indexer(self): indexer = np.array([-1, -1, 1, 2, 0, -1, 3, 4], dtype=np.int64) result = lib.get_reverse_indexer(indexer, 5) expected = np.array([4, 2, 3, 6, 7], dtype=np.int64) tm.assert_numpy_array_equal(result, expected) def test_cache_readonly_preserve_docstrings(): # GH18197 assert Index.hasnans.__doc__ is not None