Files
datafusion/python/tests/test_udaf.py
T
Jorge Leitao 46bde0bd14 Add datafusion-python (#69)
* Added Python project.

* Update python/Cargo.toml

Co-authored-by: Andy Grove <andygrove@users.noreply.github.com>

* Update python/Cargo.toml

Co-authored-by: Uwe L. Korn <xhochy@users.noreply.github.com>

* Added license and black formatting.

* License

* Fixing build.

* TesTestt

* Bumped to latest DataFusion.

* Bumped nightly.

* Bumped pyarrow in tests.

* Added some tests back.

Co-authored-by: Andy Grove <andygrove@users.noreply.github.com>
Co-authored-by: Uwe L. Korn <xhochy@users.noreply.github.com>
2021-05-04 06:24:57 -06:00

92 lines
2.8 KiB
Python

# Licensed to the Apache Software Foundation (ASF) under one
# or more contributor license agreements. See the NOTICE file
# distributed with this work for additional information
# regarding copyright ownership. The ASF licenses this file
# to you under the Apache License, Version 2.0 (the
# "License"); you may not use this file except in compliance
# with the License. You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing,
# software distributed under the License is distributed on an
# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
# KIND, either express or implied. See the License for the
# specific language governing permissions and limitations
# under the License.
import unittest
import pyarrow
import pyarrow.compute
import datafusion
f = datafusion.functions
class Accumulator:
"""
Interface of a user-defined accumulation.
"""
def __init__(self):
self._sum = pyarrow.scalar(0.0)
def to_scalars(self) -> [pyarrow.Scalar]:
return [self._sum]
def update(self, values: pyarrow.Array) -> None:
# not nice since pyarrow scalars can't be summed yet. This breaks on `None`
self._sum = pyarrow.scalar(
self._sum.as_py() + pyarrow.compute.sum(values).as_py()
)
def merge(self, states: pyarrow.Array) -> None:
# not nice since pyarrow scalars can't be summed yet. This breaks on `None`
self._sum = pyarrow.scalar(
self._sum.as_py() + pyarrow.compute.sum(states).as_py()
)
def evaluate(self) -> pyarrow.Scalar:
return self._sum
class TestCase(unittest.TestCase):
def _prepare(self):
ctx = datafusion.ExecutionContext()
# create a RecordBatch and a new DataFrame from it
batch = pyarrow.RecordBatch.from_arrays(
[pyarrow.array([1, 2, 3]), pyarrow.array([4, 4, 6])],
names=["a", "b"],
)
return ctx.create_dataframe([[batch]])
def test_aggregate(self):
df = self._prepare()
udaf = f.udaf(
Accumulator, pyarrow.float64(), pyarrow.float64(), [pyarrow.float64()]
)
df = df.aggregate([], [udaf(f.col("a"))])
# execute and collect the first (and only) batch
result = df.collect()[0]
self.assertEqual(result.column(0), pyarrow.array([1.0 + 2.0 + 3.0]))
def test_group_by(self):
df = self._prepare()
udaf = f.udaf(
Accumulator, pyarrow.float64(), pyarrow.float64(), [pyarrow.float64()]
)
df = df.aggregate([f.col("b")], [udaf(f.col("a"))])
# execute and collect the first (and only) batch
result = df.collect()[0]
self.assertEqual(result.column(1), pyarrow.array([1.0 + 2.0, 3.0]))