LightGBM/tests/python_package_test/test_arrow.py

435 строки
16 KiB
Python

# coding: utf-8
import filecmp
import os
from pathlib import Path
from typing import Any, Dict, Optional
import numpy as np
import pytest
import lightgbm as lgb
from .utils import np_assert_array_equal
# NOTE: In the AppVeyor CI, importing pyarrow fails due to an old Visual Studio version. Hence,
# we conditionally import pyarrow here (and skip tests if it cannot be imported). However, we
# don't want these tests to silently be skipped, hence, we only conditionally import when a
# specific env var is set.
if os.getenv("ALLOW_SKIP_ARROW_TESTS") == "1":
pa = pytest.importorskip("pyarrow")
else:
import pyarrow as pa # type: ignore
assert (
lgb.compat.PYARROW_INSTALLED is True
), "'pyarrow' and its dependencies must be installed to run the arrow tests"
# ----------------------------------------------------------------------------------------------- #
# UTILITIES #
# ----------------------------------------------------------------------------------------------- #
_INTEGER_TYPES = [
pa.int8(),
pa.int16(),
pa.int32(),
pa.int64(),
pa.uint8(),
pa.uint16(),
pa.uint32(),
pa.uint64(),
]
_FLOAT_TYPES = [
pa.float32(),
pa.float64(),
]
def generate_simple_arrow_table(empty_chunks: bool = False) -> pa.Table:
c: list[list[int]] = [[]] if empty_chunks else []
columns = [
pa.chunked_array(c + [[1, 2, 3]] + c + [[4, 5]] + c, type=pa.uint8()),
pa.chunked_array(c + [[1, 2, 3]] + c + [[4, 5]] + c, type=pa.int8()),
pa.chunked_array(c + [[1, 2, 3]] + c + [[4, 5]] + c, type=pa.uint16()),
pa.chunked_array(c + [[1, 2, 3]] + c + [[4, 5]] + c, type=pa.int16()),
pa.chunked_array(c + [[1, 2, 3]] + c + [[4, 5]] + c, type=pa.uint32()),
pa.chunked_array(c + [[1, 2, 3]] + c + [[4, 5]] + c, type=pa.int32()),
pa.chunked_array(c + [[1, 2, 3]] + c + [[4, 5]] + c, type=pa.uint64()),
pa.chunked_array(c + [[1, 2, 3]] + c + [[4, 5]] + c, type=pa.int64()),
pa.chunked_array(c + [[1, 2, 3]] + c + [[4, 5]] + c, type=pa.float32()),
pa.chunked_array(c + [[1, 2, 3]] + c + [[4, 5]] + c, type=pa.float64()),
pa.chunked_array(c + [[True, True, False]] + c + [[False, True]] + c, type=pa.bool_()),
]
return pa.Table.from_arrays(columns, names=[f"col_{i}" for i in range(len(columns))])
def generate_nullable_arrow_table(dtype: Any) -> pa.Table:
columns = [
pa.chunked_array([[1, None, 3, 4, 5]], type=dtype),
pa.chunked_array([[None, 2, 3, 4, 5]], type=dtype),
pa.chunked_array([[1, 2, 3, 4, None]], type=dtype),
pa.chunked_array([[None, None, None, None, None]], type=dtype),
]
return pa.Table.from_arrays(columns, names=[f"col_{i}" for i in range(len(columns))])
def generate_dummy_arrow_table() -> pa.Table:
col1 = pa.chunked_array([[1, 2, 3], [4, 5]], type=pa.uint8())
col2 = pa.chunked_array([[0.5, 0.6], [0.1, 0.8, 1.5]], type=pa.float32())
return pa.Table.from_arrays([col1, col2], names=["a", "b"])
def generate_random_arrow_table(
num_columns: int,
num_datapoints: int,
seed: int,
generate_nulls: bool = True,
values: Optional[np.ndarray] = None,
) -> pa.Table:
columns = [
generate_random_arrow_array(num_datapoints, seed + i, generate_nulls=generate_nulls, values=values)
for i in range(num_columns)
]
names = [f"col_{i}" for i in range(num_columns)]
return pa.Table.from_arrays(columns, names=names)
def generate_random_arrow_array(
num_datapoints: int,
seed: int,
generate_nulls: bool = True,
values: Optional[np.ndarray] = None,
) -> pa.ChunkedArray:
generator = np.random.default_rng(seed)
data = (
generator.standard_normal(num_datapoints)
if values is None
else generator.choice(values, size=num_datapoints, replace=True)
)
# Set random nulls
if generate_nulls:
indices = generator.choice(len(data), size=num_datapoints // 10)
data[indices] = None
# Split data into <=2 random chunks
split_points = np.sort(generator.choice(np.arange(1, num_datapoints), 2, replace=False))
split_points = np.concatenate([[0], split_points, [num_datapoints]])
chunks = [data[split_points[i] : split_points[i + 1]] for i in range(len(split_points) - 1)]
chunks = [chunk for chunk in chunks if len(chunk) > 0]
# Turn chunks into array
return pa.chunked_array([data], type=pa.float32())
def dummy_dataset_params() -> Dict[str, Any]:
return {
"min_data_in_bin": 1,
"min_data_in_leaf": 1,
}
# ----------------------------------------------------------------------------------------------- #
# UNIT TESTS #
# ----------------------------------------------------------------------------------------------- #
# ------------------------------------------- DATASET ------------------------------------------- #
def assert_datasets_equal(tmp_path: Path, lhs: lgb.Dataset, rhs: lgb.Dataset):
lhs._dump_text(tmp_path / "arrow.txt")
rhs._dump_text(tmp_path / "pandas.txt")
assert filecmp.cmp(tmp_path / "arrow.txt", tmp_path / "pandas.txt")
@pytest.mark.parametrize(
("arrow_table_fn", "dataset_params"),
[ # Use lambda functions here to minimize memory consumption
(lambda: generate_simple_arrow_table(), dummy_dataset_params()),
(lambda: generate_simple_arrow_table(empty_chunks=True), dummy_dataset_params()),
(lambda: generate_dummy_arrow_table(), dummy_dataset_params()),
(lambda: generate_nullable_arrow_table(pa.float32()), dummy_dataset_params()),
(lambda: generate_nullable_arrow_table(pa.int32()), dummy_dataset_params()),
(lambda: generate_random_arrow_table(3, 1000, 42), {}),
(lambda: generate_random_arrow_table(100, 10000, 43), {}),
],
)
def test_dataset_construct_fuzzy(tmp_path, arrow_table_fn, dataset_params):
arrow_table = arrow_table_fn()
arrow_dataset = lgb.Dataset(arrow_table, params=dataset_params)
arrow_dataset.construct()
pandas_dataset = lgb.Dataset(arrow_table.to_pandas(), params=dataset_params)
pandas_dataset.construct()
assert_datasets_equal(tmp_path, arrow_dataset, pandas_dataset)
def test_dataset_construct_fuzzy_boolean(tmp_path):
boolean_data = generate_random_arrow_table(10, 10000, 42, generate_nulls=False, values=np.array([True, False]))
float_schema = pa.schema([pa.field(f"col_{i}", pa.float32()) for i in range(len(boolean_data.columns))])
float_data = boolean_data.cast(float_schema)
arrow_dataset = lgb.Dataset(boolean_data)
arrow_dataset.construct()
pandas_dataset = lgb.Dataset(float_data.to_pandas())
pandas_dataset.construct()
assert_datasets_equal(tmp_path, arrow_dataset, pandas_dataset)
# -------------------------------------------- FIELDS ------------------------------------------- #
def test_dataset_construct_fields_fuzzy():
arrow_table = generate_random_arrow_table(3, 1000, 42)
arrow_labels = generate_random_arrow_array(1000, 42, generate_nulls=False)
arrow_weights = generate_random_arrow_array(1000, 42, generate_nulls=False)
arrow_groups = pa.chunked_array([[300, 400, 50], [250]], type=pa.int32())
arrow_dataset = lgb.Dataset(arrow_table, label=arrow_labels, weight=arrow_weights, group=arrow_groups)
arrow_dataset.construct()
pandas_dataset = lgb.Dataset(
arrow_table.to_pandas(),
label=arrow_labels.to_numpy(),
weight=arrow_weights.to_numpy(),
group=arrow_groups.to_numpy(),
)
pandas_dataset.construct()
# Check for equality
for field in ("label", "weight", "group"):
np_assert_array_equal(arrow_dataset.get_field(field), pandas_dataset.get_field(field), strict=True)
np_assert_array_equal(arrow_dataset.get_label(), pandas_dataset.get_label(), strict=True)
np_assert_array_equal(arrow_dataset.get_weight(), pandas_dataset.get_weight(), strict=True)
# -------------------------------------------- LABELS ------------------------------------------- #
@pytest.mark.parametrize(
["array_type", "label_data"],
[
(pa.array, [0, 1, 0, 0, 1]),
(pa.chunked_array, [[0], [1, 0, 0, 1]]),
(pa.chunked_array, [[], [0], [1, 0, 0, 1]]),
(pa.chunked_array, [[0], [], [1, 0], [], [], [0, 1], []]),
],
)
@pytest.mark.parametrize("arrow_type", _INTEGER_TYPES + _FLOAT_TYPES)
def test_dataset_construct_labels(array_type, label_data, arrow_type):
data = generate_dummy_arrow_table()
labels = array_type(label_data, type=arrow_type)
dataset = lgb.Dataset(data, label=labels, params=dummy_dataset_params())
dataset.construct()
expected = np.array([0, 1, 0, 0, 1], dtype=np.float32)
np_assert_array_equal(expected, dataset.get_label(), strict=True)
@pytest.mark.parametrize(
["array_type", "label_data"],
[
(pa.array, [False, True, False, False, True]),
(pa.chunked_array, [[False], [True, False, False, True]]),
(pa.chunked_array, [[], [False], [True, False, False, True]]),
(pa.chunked_array, [[False], [], [True, False], [], [], [False, True], []]),
],
)
def test_dataset_construct_labels_boolean(array_type, label_data):
data = generate_dummy_arrow_table()
labels = array_type(label_data, type=pa.bool_())
dataset = lgb.Dataset(data, label=labels, params=dummy_dataset_params())
dataset.construct()
expected = np.array([0, 1, 0, 0, 1], dtype=np.float32)
np_assert_array_equal(expected, dataset.get_label(), strict=True)
# ------------------------------------------- WEIGHTS ------------------------------------------- #
def test_dataset_construct_weights_none():
data = generate_dummy_arrow_table()
weight = pa.array([1, 1, 1, 1, 1])
dataset = lgb.Dataset(data, weight=weight, params=dummy_dataset_params())
dataset.construct()
assert dataset.get_weight() is None
assert dataset.get_field("weight") is None
@pytest.mark.parametrize(
["array_type", "weight_data"],
[
(pa.array, [3, 0.7, 1.5, 0.5, 0.1]),
(pa.chunked_array, [[3], [0.7, 1.5, 0.5, 0.1]]),
(pa.chunked_array, [[], [3], [0.7, 1.5, 0.5, 0.1]]),
(pa.chunked_array, [[3], [0.7], [], [], [1.5, 0.5, 0.1], []]),
],
)
@pytest.mark.parametrize("arrow_type", _FLOAT_TYPES)
def test_dataset_construct_weights(array_type, weight_data, arrow_type):
data = generate_dummy_arrow_table()
weights = array_type(weight_data, type=arrow_type)
dataset = lgb.Dataset(data, weight=weights, params=dummy_dataset_params())
dataset.construct()
expected = np.array([3, 0.7, 1.5, 0.5, 0.1], dtype=np.float32)
np_assert_array_equal(expected, dataset.get_weight(), strict=True)
# -------------------------------------------- GROUPS ------------------------------------------- #
@pytest.mark.parametrize(
["array_type", "group_data"],
[
(pa.array, [2, 3]),
(pa.chunked_array, [[2], [3]]),
(pa.chunked_array, [[], [2, 3]]),
(pa.chunked_array, [[2], [], [3], []]),
],
)
@pytest.mark.parametrize("arrow_type", _INTEGER_TYPES)
def test_dataset_construct_groups(array_type, group_data, arrow_type):
data = generate_dummy_arrow_table()
groups = array_type(group_data, type=arrow_type)
dataset = lgb.Dataset(data, group=groups, params=dummy_dataset_params())
dataset.construct()
expected = np.array([0, 2, 5], dtype=np.int32)
np_assert_array_equal(expected, dataset.get_field("group"), strict=True)
# ----------------------------------------- INIT SCORES ----------------------------------------- #
@pytest.mark.parametrize(
["array_type", "init_score_data"],
[
(pa.array, [0, 1, 2, 3, 3]),
(pa.chunked_array, [[0, 1, 2], [3, 3]]),
(pa.chunked_array, [[], [0, 1, 2], [3, 3]]),
(pa.chunked_array, [[0, 1], [], [], [2], [3, 3], []]),
],
)
@pytest.mark.parametrize("arrow_type", _INTEGER_TYPES + _FLOAT_TYPES)
def test_dataset_construct_init_scores_array(array_type: Any, init_score_data: Any, arrow_type: Any):
data = generate_dummy_arrow_table()
init_scores = array_type(init_score_data, type=arrow_type)
dataset = lgb.Dataset(data, init_score=init_scores, params=dummy_dataset_params())
dataset.construct()
expected = np.array([0, 1, 2, 3, 3], dtype=np.float64)
np_assert_array_equal(expected, dataset.get_init_score(), strict=True)
def test_dataset_construct_init_scores_table():
data = generate_dummy_arrow_table()
init_scores = pa.Table.from_arrays(
[
generate_random_arrow_array(5, seed=1, generate_nulls=False),
generate_random_arrow_array(5, seed=2, generate_nulls=False),
generate_random_arrow_array(5, seed=3, generate_nulls=False),
],
names=["a", "b", "c"],
)
dataset = lgb.Dataset(data, init_score=init_scores, params=dummy_dataset_params())
dataset.construct()
actual = dataset.get_init_score()
expected = init_scores.to_pandas().to_numpy().astype(np.float64)
np_assert_array_equal(expected, actual, strict=True)
# ------------------------------------------ PREDICTION ----------------------------------------- #
def assert_equal_predict_arrow_pandas(booster: lgb.Booster, data: pa.Table):
p_arrow = booster.predict(data)
p_pandas = booster.predict(data.to_pandas())
np_assert_array_equal(p_arrow, p_pandas, strict=True)
p_raw_arrow = booster.predict(data, raw_score=True)
p_raw_pandas = booster.predict(data.to_pandas(), raw_score=True)
np_assert_array_equal(p_raw_arrow, p_raw_pandas, strict=True)
p_leaf_arrow = booster.predict(data, pred_leaf=True)
p_leaf_pandas = booster.predict(data.to_pandas(), pred_leaf=True)
np_assert_array_equal(p_leaf_arrow, p_leaf_pandas, strict=True)
p_pred_contrib_arrow = booster.predict(data, pred_contrib=True)
p_pred_contrib_pandas = booster.predict(data.to_pandas(), pred_contrib=True)
np_assert_array_equal(p_pred_contrib_arrow, p_pred_contrib_pandas, strict=True)
p_first_iter_arrow = booster.predict(data, start_iteration=0, num_iteration=1, raw_score=True)
p_first_iter_pandas = booster.predict(data.to_pandas(), start_iteration=0, num_iteration=1, raw_score=True)
np_assert_array_equal(p_first_iter_arrow, p_first_iter_pandas, strict=True)
def test_predict_regression():
data_float = generate_random_arrow_table(10, 10000, 42)
data_bool = generate_random_arrow_table(1, 10000, 42, generate_nulls=False, values=np.array([True, False]))
data = pa.Table.from_arrays(data_float.columns + data_bool.columns, names=data_float.schema.names + ["col_bool"])
dataset = lgb.Dataset(
data,
label=generate_random_arrow_array(10000, 43, generate_nulls=False),
params=dummy_dataset_params(),
)
booster = lgb.train(
{"objective": "regression", "num_leaves": 7},
dataset,
num_boost_round=5,
)
assert_equal_predict_arrow_pandas(booster, data)
def test_predict_binary_classification():
data = generate_random_arrow_table(10, 10000, 42)
dataset = lgb.Dataset(
data,
label=generate_random_arrow_array(10000, 43, generate_nulls=False, values=np.arange(2)),
params=dummy_dataset_params(),
)
booster = lgb.train(
{"objective": "binary", "num_leaves": 7},
dataset,
num_boost_round=5,
)
assert_equal_predict_arrow_pandas(booster, data)
def test_predict_multiclass_classification():
data = generate_random_arrow_table(10, 10000, 42)
dataset = lgb.Dataset(
data,
label=generate_random_arrow_array(10000, 43, generate_nulls=False, values=np.arange(5)),
params=dummy_dataset_params(),
)
booster = lgb.train(
{"objective": "multiclass", "num_leaves": 7, "num_class": 5},
dataset,
num_boost_round=5,
)
assert_equal_predict_arrow_pandas(booster, data)
def test_predict_ranking():
data = generate_random_arrow_table(10, 10000, 42)
dataset = lgb.Dataset(
data,
label=generate_random_arrow_array(10000, 43, generate_nulls=False, values=np.arange(4)),
group=np.array([1000, 2000, 3000, 4000]),
params=dummy_dataset_params(),
)
booster = lgb.train(
{"objective": "lambdarank", "num_leaves": 7},
dataset,
num_boost_round=5,
)
assert_equal_predict_arrow_pandas(booster, data)