Function test_byte_stream_split

python/pyarrow/tests/parquet/test_basic.py:351–386

()

def test_byte_stream_split():
    # This is only a smoke test.
    arr_float = pa.array(list(map(float, range(100))))
    arr_int = pa.array(list(map(int, range(100))))
    arr_bool = pa.array([True, False] * 50)
    data_float = [arr_float, arr_float]
    table = pa.Table.from_arrays(data_float, names=['a', 'b'])

    # Check with byte_stream_split for both columns.
    _check_roundtrip(table, expected=table, compression="gzip",
                     use_dictionary=False, use_byte_stream_split=True)

    # Check with byte_stream_split for column 'b' and dictionary
    # for column 'a'.
    _check_roundtrip(table, expected=table, compression="gzip",
                     use_dictionary=['a'],
                     use_byte_stream_split=['b'])

    # Check with a collision for both columns.
    _check_roundtrip(table, expected=table, compression="gzip",
                     use_dictionary=['a', 'b'],
                     use_byte_stream_split=['a', 'b'])

    # Check with mixed column types.
    mixed_table = pa.Table.from_arrays([arr_float, arr_float, arr_int, arr_int],
                                       names=['a', 'b', 'c', 'd'])
    _check_roundtrip(mixed_table, expected=mixed_table,
                     use_dictionary=['b', 'd'],
                     use_byte_stream_split=['a', 'c'])

    # Try to use the wrong data type with the byte_stream_split encoding.
    # This should throw an exception.
    table = pa.Table.from_arrays([arr_bool], names=['tmp'])
    with pytest.raises(IOError, match='BYTE_STREAM_SPLIT only supports'):
        _check_roundtrip(table, expected=table, use_byte_stream_split=True,
                         use_dictionary=False)


def test_store_decimal_as_integer(tempdir):