| 3882 | |
| 3883 | |
| 3884 | def test_diff(): |
| 3885 | df = pd.DataFrame(np.random.randn(100, 5), columns=list("abcde")) |
| 3886 | ddf = dd.from_pandas(df, 5) |
| 3887 | |
| 3888 | assert_eq(ddf.diff(), df.diff()) |
| 3889 | assert_eq(ddf.diff(0), df.diff(0)) |
| 3890 | assert_eq(ddf.diff(2), df.diff(2)) |
| 3891 | assert_eq(ddf.diff(-2), df.diff(-2)) |
| 3892 | |
| 3893 | assert_eq(ddf.diff(2, axis=1), df.diff(2, axis=1)) |
| 3894 | |
| 3895 | assert_eq(ddf.a.diff(), df.a.diff()) |
| 3896 | assert_eq(ddf.a.diff(0), df.a.diff(0)) |
| 3897 | assert_eq(ddf.a.diff(2), df.a.diff(2)) |
| 3898 | assert_eq(ddf.a.diff(-2), df.a.diff(-2)) |
| 3899 | |
| 3900 | assert ddf.diff(2)._name == ddf.diff(2)._name |
| 3901 | assert ddf.diff(2)._name != ddf.diff(3)._name |
| 3902 | with pytest.raises((TypeError, ValueError)): |
| 3903 | ddf.diff(1.5) |
| 3904 | |
| 3905 | |
| 3906 | def test_shift(): |