import numpy as np from pandas import PeriodIndex import pandas._testing as tm class TestFactorize: def test_factorize_period(self): idx1 = PeriodIndex( ["2014-01", "2014-01", "2014-02", "2014-02", "2014-03", "2014-03"], freq="M", ) exp_arr = np.array([0, 0, 1, 1, 2, 2], dtype=np.intp) exp_idx = PeriodIndex(["2014-01", "2014-02", "2014-03"], freq="M") arr, idx = idx1.factorize() tm.assert_numpy_array_equal(arr, exp_arr) tm.assert_index_equal(idx, exp_idx) arr, idx = idx1.factorize(sort=True) tm.assert_numpy_array_equal(arr, exp_arr) tm.assert_index_equal(idx, exp_idx) def test_factorize_period_nonmonotonic(self): idx2 = PeriodIndex( ["2014-03", "2014-03", "2014-02", "2014-01", "2014-03", "2014-01"], freq="M", ) exp_idx = PeriodIndex(["2014-01", "2014-02", "2014-03"], freq="M") exp_arr = np.array([2, 2, 1, 0, 2, 0], dtype=np.intp) arr, idx = idx2.factorize(sort=True) tm.assert_numpy_array_equal(arr, exp_arr) tm.assert_index_equal(idx, exp_idx) exp_arr = np.array([0, 0, 1, 2, 0, 2], dtype=np.intp) exp_idx = PeriodIndex(["2014-03", "2014-02", "2014-01"], freq="M") arr, idx = idx2.factorize() tm.assert_numpy_array_equal(arr, exp_arr) tm.assert_index_equal(idx, exp_idx)