ai-content-maker/.venv/Lib/site-packages/pandas/tests/reshape/concat/test_concat.py

806 lines
27 KiB
Python

from collections import (
abc,
deque,
)
from decimal import Decimal
from warnings import (
catch_warnings,
simplefilter,
)
import numpy as np
import pytest
from pandas.errors import (
InvalidIndexError,
PerformanceWarning,
)
import pandas.util._test_decorators as td
import pandas as pd
from pandas import (
DataFrame,
Index,
MultiIndex,
PeriodIndex,
Series,
concat,
date_range,
)
import pandas._testing as tm
from pandas.core.arrays import SparseArray
from pandas.core.construction import create_series_with_explicit_dtype
from pandas.tests.extension.decimal import to_decimal
class TestConcatenate:
def test_append_concat(self):
# GH#1815
d1 = date_range("12/31/1990", "12/31/1999", freq="A-DEC")
d2 = date_range("12/31/2000", "12/31/2009", freq="A-DEC")
s1 = Series(np.random.randn(10), d1)
s2 = Series(np.random.randn(10), d2)
s1 = s1.to_period()
s2 = s2.to_period()
# drops index
result = concat([s1, s2])
assert isinstance(result.index, PeriodIndex)
assert result.index[0] == s1.index[0]
def test_concat_copy(self, using_array_manager):
df = DataFrame(np.random.randn(4, 3))
df2 = DataFrame(np.random.randint(0, 10, size=4).reshape(4, 1))
df3 = DataFrame({5: "foo"}, index=range(4))
# These are actual copies.
result = concat([df, df2, df3], axis=1, copy=True)
for arr in result._mgr.arrays:
assert arr.base is None
# These are the same.
result = concat([df, df2, df3], axis=1, copy=False)
for arr in result._mgr.arrays:
if arr.dtype.kind == "f":
assert arr.base is df._mgr.arrays[0].base
elif arr.dtype.kind in ["i", "u"]:
assert arr.base is df2._mgr.arrays[0].base
elif arr.dtype == object:
if using_array_manager:
# we get the same array object, which has no base
assert arr is df3._mgr.arrays[0]
else:
assert arr.base is not None
# Float block was consolidated.
df4 = DataFrame(np.random.randn(4, 1))
result = concat([df, df2, df3, df4], axis=1, copy=False)
for arr in result._mgr.arrays:
if arr.dtype.kind == "f":
if using_array_manager:
# this is a view on some array in either df or df4
assert any(
np.shares_memory(arr, other)
for other in df._mgr.arrays + df4._mgr.arrays
)
else:
# the block was consolidated, so we got a copy anyway
assert arr.base is None
elif arr.dtype.kind in ["i", "u"]:
assert arr.base is df2._mgr.arrays[0].base
elif arr.dtype == object:
# this is a view on df3
assert any(np.shares_memory(arr, other) for other in df3._mgr.arrays)
def test_concat_with_group_keys(self):
# axis=0
df = DataFrame(np.random.randn(3, 4))
df2 = DataFrame(np.random.randn(4, 4))
result = concat([df, df2], keys=[0, 1])
exp_index = MultiIndex.from_arrays(
[[0, 0, 0, 1, 1, 1, 1], [0, 1, 2, 0, 1, 2, 3]]
)
expected = DataFrame(np.r_[df.values, df2.values], index=exp_index)
tm.assert_frame_equal(result, expected)
result = concat([df, df], keys=[0, 1])
exp_index2 = MultiIndex.from_arrays([[0, 0, 0, 1, 1, 1], [0, 1, 2, 0, 1, 2]])
expected = DataFrame(np.r_[df.values, df.values], index=exp_index2)
tm.assert_frame_equal(result, expected)
# axis=1
df = DataFrame(np.random.randn(4, 3))
df2 = DataFrame(np.random.randn(4, 4))
result = concat([df, df2], keys=[0, 1], axis=1)
expected = DataFrame(np.c_[df.values, df2.values], columns=exp_index)
tm.assert_frame_equal(result, expected)
result = concat([df, df], keys=[0, 1], axis=1)
expected = DataFrame(np.c_[df.values, df.values], columns=exp_index2)
tm.assert_frame_equal(result, expected)
def test_concat_keys_specific_levels(self):
df = DataFrame(np.random.randn(10, 4))
pieces = [df.iloc[:, [0, 1]], df.iloc[:, [2]], df.iloc[:, [3]]]
level = ["three", "two", "one", "zero"]
result = concat(
pieces,
axis=1,
keys=["one", "two", "three"],
levels=[level],
names=["group_key"],
)
tm.assert_index_equal(result.columns.levels[0], Index(level, name="group_key"))
tm.assert_index_equal(result.columns.levels[1], Index([0, 1, 2, 3]))
assert result.columns.names == ["group_key", None]
@pytest.mark.parametrize("mapping", ["mapping", "dict"])
def test_concat_mapping(self, mapping, non_dict_mapping_subclass):
constructor = dict if mapping == "dict" else non_dict_mapping_subclass
frames = constructor(
{
"foo": DataFrame(np.random.randn(4, 3)),
"bar": DataFrame(np.random.randn(4, 3)),
"baz": DataFrame(np.random.randn(4, 3)),
"qux": DataFrame(np.random.randn(4, 3)),
}
)
sorted_keys = list(frames.keys())
result = concat(frames)
expected = concat([frames[k] for k in sorted_keys], keys=sorted_keys)
tm.assert_frame_equal(result, expected)
result = concat(frames, axis=1)
expected = concat([frames[k] for k in sorted_keys], keys=sorted_keys, axis=1)
tm.assert_frame_equal(result, expected)
keys = ["baz", "foo", "bar"]
result = concat(frames, keys=keys)
expected = concat([frames[k] for k in keys], keys=keys)
tm.assert_frame_equal(result, expected)
def test_concat_keys_and_levels(self):
df = DataFrame(np.random.randn(1, 3))
df2 = DataFrame(np.random.randn(1, 4))
levels = [["foo", "baz"], ["one", "two"]]
names = ["first", "second"]
result = concat(
[df, df2, df, df2],
keys=[("foo", "one"), ("foo", "two"), ("baz", "one"), ("baz", "two")],
levels=levels,
names=names,
)
expected = concat([df, df2, df, df2])
exp_index = MultiIndex(
levels=levels + [[0]],
codes=[[0, 0, 1, 1], [0, 1, 0, 1], [0, 0, 0, 0]],
names=names + [None],
)
expected.index = exp_index
tm.assert_frame_equal(result, expected)
# no names
result = concat(
[df, df2, df, df2],
keys=[("foo", "one"), ("foo", "two"), ("baz", "one"), ("baz", "two")],
levels=levels,
)
assert result.index.names == (None,) * 3
# no levels
result = concat(
[df, df2, df, df2],
keys=[("foo", "one"), ("foo", "two"), ("baz", "one"), ("baz", "two")],
names=["first", "second"],
)
assert result.index.names == ("first", "second", None)
tm.assert_index_equal(
result.index.levels[0], Index(["baz", "foo"], name="first")
)
def test_concat_keys_levels_no_overlap(self):
# GH #1406
df = DataFrame(np.random.randn(1, 3), index=["a"])
df2 = DataFrame(np.random.randn(1, 4), index=["b"])
msg = "Values not found in passed level"
with pytest.raises(ValueError, match=msg):
concat([df, df], keys=["one", "two"], levels=[["foo", "bar", "baz"]])
msg = "Key one not in level"
with pytest.raises(ValueError, match=msg):
concat([df, df2], keys=["one", "two"], levels=[["foo", "bar", "baz"]])
def test_crossed_dtypes_weird_corner(self):
columns = ["A", "B", "C", "D"]
df1 = DataFrame(
{
"A": np.array([1, 2, 3, 4], dtype="f8"),
"B": np.array([1, 2, 3, 4], dtype="i8"),
"C": np.array([1, 2, 3, 4], dtype="f8"),
"D": np.array([1, 2, 3, 4], dtype="i8"),
},
columns=columns,
)
df2 = DataFrame(
{
"A": np.array([1, 2, 3, 4], dtype="i8"),
"B": np.array([1, 2, 3, 4], dtype="f8"),
"C": np.array([1, 2, 3, 4], dtype="i8"),
"D": np.array([1, 2, 3, 4], dtype="f8"),
},
columns=columns,
)
appended = concat([df1, df2], ignore_index=True)
expected = DataFrame(
np.concatenate([df1.values, df2.values], axis=0), columns=columns
)
tm.assert_frame_equal(appended, expected)
df = DataFrame(np.random.randn(1, 3), index=["a"])
df2 = DataFrame(np.random.randn(1, 4), index=["b"])
result = concat([df, df2], keys=["one", "two"], names=["first", "second"])
assert result.index.names == ("first", "second")
def test_with_mixed_tuples(self, sort):
# 10697
# columns have mixed tuples, so handle properly
df1 = DataFrame({"A": "foo", ("B", 1): "bar"}, index=range(2))
df2 = DataFrame({"B": "foo", ("B", 1): "bar"}, index=range(2))
# it works
concat([df1, df2], sort=sort)
def test_concat_mixed_objs(self):
# concat mixed series/frames
# G2385
# axis 1
index = date_range("01-Jan-2013", periods=10, freq="H")
arr = np.arange(10, dtype="int64")
s1 = Series(arr, index=index)
s2 = Series(arr, index=index)
df = DataFrame(arr.reshape(-1, 1), index=index)
expected = DataFrame(
np.repeat(arr, 2).reshape(-1, 2), index=index, columns=[0, 0]
)
result = concat([df, df], axis=1)
tm.assert_frame_equal(result, expected)
expected = DataFrame(
np.repeat(arr, 2).reshape(-1, 2), index=index, columns=[0, 1]
)
result = concat([s1, s2], axis=1)
tm.assert_frame_equal(result, expected)
expected = DataFrame(
np.repeat(arr, 3).reshape(-1, 3), index=index, columns=[0, 1, 2]
)
result = concat([s1, s2, s1], axis=1)
tm.assert_frame_equal(result, expected)
expected = DataFrame(
np.repeat(arr, 5).reshape(-1, 5), index=index, columns=[0, 0, 1, 2, 3]
)
result = concat([s1, df, s2, s2, s1], axis=1)
tm.assert_frame_equal(result, expected)
# with names
s1.name = "foo"
expected = DataFrame(
np.repeat(arr, 3).reshape(-1, 3), index=index, columns=["foo", 0, 0]
)
result = concat([s1, df, s2], axis=1)
tm.assert_frame_equal(result, expected)
s2.name = "bar"
expected = DataFrame(
np.repeat(arr, 3).reshape(-1, 3), index=index, columns=["foo", 0, "bar"]
)
result = concat([s1, df, s2], axis=1)
tm.assert_frame_equal(result, expected)
# ignore index
expected = DataFrame(
np.repeat(arr, 3).reshape(-1, 3), index=index, columns=[0, 1, 2]
)
result = concat([s1, df, s2], axis=1, ignore_index=True)
tm.assert_frame_equal(result, expected)
# axis 0
expected = DataFrame(
np.tile(arr, 3).reshape(-1, 1), index=index.tolist() * 3, columns=[0]
)
result = concat([s1, df, s2])
tm.assert_frame_equal(result, expected)
expected = DataFrame(np.tile(arr, 3).reshape(-1, 1), columns=[0])
result = concat([s1, df, s2], ignore_index=True)
tm.assert_frame_equal(result, expected)
def test_dtype_coerceion(self):
# 12411
df = DataFrame({"date": [pd.Timestamp("20130101").tz_localize("UTC"), pd.NaT]})
result = concat([df.iloc[[0]], df.iloc[[1]]])
tm.assert_series_equal(result.dtypes, df.dtypes)
# 12045
import datetime
df = DataFrame(
{"date": [datetime.datetime(2012, 1, 1), datetime.datetime(1012, 1, 2)]}
)
result = concat([df.iloc[[0]], df.iloc[[1]]])
tm.assert_series_equal(result.dtypes, df.dtypes)
# 11594
df = DataFrame({"text": ["some words"] + [None] * 9})
result = concat([df.iloc[[0]], df.iloc[[1]]])
tm.assert_series_equal(result.dtypes, df.dtypes)
def test_concat_single_with_key(self):
df = DataFrame(np.random.randn(10, 4))
result = concat([df], keys=["foo"])
expected = concat([df, df], keys=["foo", "bar"])
tm.assert_frame_equal(result, expected[:10])
def test_concat_no_items_raises(self):
with pytest.raises(ValueError, match="No objects to concatenate"):
concat([])
def test_concat_exclude_none(self):
df = DataFrame(np.random.randn(10, 4))
pieces = [df[:5], None, None, df[5:]]
result = concat(pieces)
tm.assert_frame_equal(result, df)
with pytest.raises(ValueError, match="All objects passed were None"):
concat([None, None])
def test_concat_keys_with_none(self):
# #1649
df0 = DataFrame([[10, 20, 30], [10, 20, 30], [10, 20, 30]])
result = concat({"a": None, "b": df0, "c": df0[:2], "d": df0[:1], "e": df0})
expected = concat({"b": df0, "c": df0[:2], "d": df0[:1], "e": df0})
tm.assert_frame_equal(result, expected)
result = concat(
[None, df0, df0[:2], df0[:1], df0], keys=["a", "b", "c", "d", "e"]
)
expected = concat([df0, df0[:2], df0[:1], df0], keys=["b", "c", "d", "e"])
tm.assert_frame_equal(result, expected)
def test_concat_bug_1719(self):
ts1 = tm.makeTimeSeries()
ts2 = tm.makeTimeSeries()[::2]
# to join with union
# these two are of different length!
left = concat([ts1, ts2], join="outer", axis=1)
right = concat([ts2, ts1], join="outer", axis=1)
assert len(left) == len(right)
def test_concat_bug_2972(self):
ts0 = Series(np.zeros(5))
ts1 = Series(np.ones(5))
ts0.name = ts1.name = "same name"
result = concat([ts0, ts1], axis=1)
expected = DataFrame({0: ts0, 1: ts1})
expected.columns = ["same name", "same name"]
tm.assert_frame_equal(result, expected)
def test_concat_bug_3602(self):
# GH 3602, duplicate columns
df1 = DataFrame(
{
"firmNo": [0, 0, 0, 0],
"prc": [6, 6, 6, 6],
"stringvar": ["rrr", "rrr", "rrr", "rrr"],
}
)
df2 = DataFrame(
{"C": [9, 10, 11, 12], "misc": [1, 2, 3, 4], "prc": [6, 6, 6, 6]}
)
expected = DataFrame(
[
[0, 6, "rrr", 9, 1, 6],
[0, 6, "rrr", 10, 2, 6],
[0, 6, "rrr", 11, 3, 6],
[0, 6, "rrr", 12, 4, 6],
]
)
expected.columns = ["firmNo", "prc", "stringvar", "C", "misc", "prc"]
result = concat([df1, df2], axis=1)
tm.assert_frame_equal(result, expected)
def test_concat_iterables(self):
# GH8645 check concat works with tuples, list, generators, and weird
# stuff like deque and custom iterables
df1 = DataFrame([1, 2, 3])
df2 = DataFrame([4, 5, 6])
expected = DataFrame([1, 2, 3, 4, 5, 6])
tm.assert_frame_equal(concat((df1, df2), ignore_index=True), expected)
tm.assert_frame_equal(concat([df1, df2], ignore_index=True), expected)
tm.assert_frame_equal(
concat((df for df in (df1, df2)), ignore_index=True), expected
)
tm.assert_frame_equal(concat(deque((df1, df2)), ignore_index=True), expected)
class CustomIterator1:
def __len__(self) -> int:
return 2
def __getitem__(self, index):
try:
return {0: df1, 1: df2}[index]
except KeyError as err:
raise IndexError from err
tm.assert_frame_equal(concat(CustomIterator1(), ignore_index=True), expected)
class CustomIterator2(abc.Iterable):
def __iter__(self):
yield df1
yield df2
tm.assert_frame_equal(concat(CustomIterator2(), ignore_index=True), expected)
def test_concat_order(self):
# GH 17344, GH#47331
dfs = [DataFrame(index=range(3), columns=["a", 1, None])]
dfs += [DataFrame(index=range(3), columns=[None, 1, "a"]) for _ in range(100)]
result = concat(dfs, sort=True).columns
expected = Index([1, "a", None])
tm.assert_index_equal(result, expected)
def test_concat_different_extension_dtypes_upcasts(self):
a = Series(pd.array([1, 2], dtype="Int64"))
b = Series(to_decimal([1, 2]))
result = concat([a, b], ignore_index=True)
expected = Series([1, 2, Decimal(1), Decimal(2)], dtype=object)
tm.assert_series_equal(result, expected)
def test_concat_ordered_dict(self):
# GH 21510
expected = concat(
[Series(range(3)), Series(range(4))], keys=["First", "Another"]
)
result = concat({"First": Series(range(3)), "Another": Series(range(4))})
tm.assert_series_equal(result, expected)
def test_concat_duplicate_indices_raise(self):
# GH 45888: test raise for concat DataFrames with duplicate indices
# https://github.com/pandas-dev/pandas/issues/36263
df1 = DataFrame(np.random.randn(5), index=[0, 1, 2, 3, 3], columns=["a"])
df2 = DataFrame(np.random.randn(5), index=[0, 1, 2, 2, 4], columns=["b"])
msg = "Reindexing only valid with uniquely valued Index objects"
with pytest.raises(InvalidIndexError, match=msg):
concat([df1, df2], axis=1)
@pytest.mark.parametrize("pdt", [Series, DataFrame])
@pytest.mark.parametrize("dt", np.sctypes["float"])
def test_concat_no_unnecessary_upcast(dt, pdt):
# GH 13247
dims = pdt(dtype=object).ndim
dfs = [
pdt(np.array([1], dtype=dt, ndmin=dims)),
pdt(np.array([np.nan], dtype=dt, ndmin=dims)),
pdt(np.array([5], dtype=dt, ndmin=dims)),
]
x = concat(dfs)
assert x.values.dtype == dt
@pytest.mark.parametrize("pdt", [create_series_with_explicit_dtype, DataFrame])
@pytest.mark.parametrize("dt", np.sctypes["int"])
def test_concat_will_upcast(dt, pdt):
with catch_warnings(record=True):
dims = pdt().ndim
dfs = [
pdt(np.array([1], dtype=dt, ndmin=dims)),
pdt(np.array([np.nan], ndmin=dims)),
pdt(np.array([5], dtype=dt, ndmin=dims)),
]
x = concat(dfs)
assert x.values.dtype == "float64"
def test_concat_empty_and_non_empty_frame_regression():
# GH 18178 regression test
df1 = DataFrame({"foo": [1]})
df2 = DataFrame({"foo": []})
expected = DataFrame({"foo": [1.0]})
result = concat([df1, df2])
tm.assert_frame_equal(result, expected)
def test_concat_sparse():
# GH 23557
a = Series(SparseArray([0, 1, 2]))
expected = DataFrame(data=[[0, 0], [1, 1], [2, 2]]).astype(
pd.SparseDtype(np.int64, 0)
)
result = concat([a, a], axis=1)
tm.assert_frame_equal(result, expected)
def test_concat_dense_sparse():
# GH 30668
dtype = pd.SparseDtype(np.float64, None)
a = Series(pd.arrays.SparseArray([1, None]), dtype=dtype)
b = Series([1], dtype=float)
expected = Series(data=[1, None, 1], index=[0, 1, 0]).astype(dtype)
result = concat([a, b], axis=0)
tm.assert_series_equal(result, expected)
@pytest.mark.parametrize("keys", [["e", "f", "f"], ["f", "e", "f"]])
def test_duplicate_keys(keys):
# GH 33654
df = DataFrame({"a": [1, 2, 3], "b": [4, 5, 6]})
s1 = Series([7, 8, 9], name="c")
s2 = Series([10, 11, 12], name="d")
result = concat([df, s1, s2], axis=1, keys=keys)
expected_values = [[1, 4, 7, 10], [2, 5, 8, 11], [3, 6, 9, 12]]
expected_columns = MultiIndex.from_tuples(
[(keys[0], "a"), (keys[0], "b"), (keys[1], "c"), (keys[2], "d")]
)
expected = DataFrame(expected_values, columns=expected_columns)
tm.assert_frame_equal(result, expected)
def test_duplicate_keys_same_frame():
# GH 43595
keys = ["e", "e"]
df = DataFrame({"a": [1, 2, 3], "b": [4, 5, 6]})
result = concat([df, df], axis=1, keys=keys)
expected_values = [[1, 4, 1, 4], [2, 5, 2, 5], [3, 6, 3, 6]]
expected_columns = MultiIndex.from_tuples(
[(keys[0], "a"), (keys[0], "b"), (keys[1], "a"), (keys[1], "b")]
)
expected = DataFrame(expected_values, columns=expected_columns)
with catch_warnings():
# result.columns not sorted, resulting in performance warning
simplefilter("ignore", PerformanceWarning)
tm.assert_frame_equal(result, expected)
@pytest.mark.parametrize(
"obj",
[
tm.SubclassedDataFrame({"A": np.arange(0, 10)}),
tm.SubclassedSeries(np.arange(0, 10), name="A"),
],
)
def test_concat_preserves_subclass(obj):
# GH28330 -- preserve subclass
result = concat([obj, obj])
assert isinstance(result, type(obj))
def test_concat_frame_axis0_extension_dtypes():
# preserve extension dtype (through common_dtype mechanism)
df1 = DataFrame({"a": pd.array([1, 2, 3], dtype="Int64")})
df2 = DataFrame({"a": np.array([4, 5, 6])})
result = concat([df1, df2], ignore_index=True)
expected = DataFrame({"a": [1, 2, 3, 4, 5, 6]}, dtype="Int64")
tm.assert_frame_equal(result, expected)
result = concat([df2, df1], ignore_index=True)
expected = DataFrame({"a": [4, 5, 6, 1, 2, 3]}, dtype="Int64")
tm.assert_frame_equal(result, expected)
def test_concat_preserves_extension_int64_dtype():
# GH 24768
df_a = DataFrame({"a": [-1]}, dtype="Int64")
df_b = DataFrame({"b": [1]}, dtype="Int64")
result = concat([df_a, df_b], ignore_index=True)
expected = DataFrame({"a": [-1, None], "b": [None, 1]}, dtype="Int64")
tm.assert_frame_equal(result, expected)
@pytest.mark.parametrize(
"dtype1,dtype2,expected_dtype",
[
("bool", "bool", "bool"),
("boolean", "bool", "boolean"),
("bool", "boolean", "boolean"),
("boolean", "boolean", "boolean"),
],
)
def test_concat_bool_types(dtype1, dtype2, expected_dtype):
# GH 42800
ser1 = Series([True, False], dtype=dtype1)
ser2 = Series([False, True], dtype=dtype2)
result = concat([ser1, ser2], ignore_index=True)
expected = Series([True, False, False, True], dtype=expected_dtype)
tm.assert_series_equal(result, expected)
@pytest.mark.parametrize(
("keys", "integrity"),
[
(["red"] * 3, True),
(["red"] * 3, False),
(["red", "blue", "red"], False),
(["red", "blue", "red"], True),
],
)
def test_concat_repeated_keys(keys, integrity):
# GH: 20816
series_list = [Series({"a": 1}), Series({"b": 2}), Series({"c": 3})]
result = concat(series_list, keys=keys, verify_integrity=integrity)
tuples = list(zip(keys, ["a", "b", "c"]))
expected = Series([1, 2, 3], index=MultiIndex.from_tuples(tuples))
tm.assert_series_equal(result, expected)
def test_concat_null_object_with_dti():
# GH#40841
dti = pd.DatetimeIndex(
["2021-04-08 21:21:14+00:00"], dtype="datetime64[ns, UTC]", name="Time (UTC)"
)
right = DataFrame(data={"C": [0.5274]}, index=dti)
idx = Index([None], dtype="object", name="Maybe Time (UTC)")
left = DataFrame(data={"A": [None], "B": [np.nan]}, index=idx)
result = concat([left, right], axis="columns")
exp_index = Index([None, dti[0]], dtype=object)
expected = DataFrame(
{"A": [None, None], "B": [np.nan, np.nan], "C": [np.nan, 0.5274]},
index=exp_index,
)
tm.assert_frame_equal(result, expected)
def test_concat_multiindex_with_empty_rangeindex():
# GH#41234
mi = MultiIndex.from_tuples([("B", 1), ("C", 1)])
df1 = DataFrame([[1, 2]], columns=mi)
df2 = DataFrame(index=[1], columns=pd.RangeIndex(0))
result = concat([df1, df2])
expected = DataFrame([[1, 2], [np.nan, np.nan]], columns=mi)
tm.assert_frame_equal(result, expected)
def test_concat_posargs_deprecation():
# https://github.com/pandas-dev/pandas/issues/41485
df = DataFrame([[1, 2, 3]], index=["a"])
df2 = DataFrame([[4, 5, 6]], index=["b"])
msg = (
"In a future version of pandas all arguments of concat "
"except for the argument 'objs' will be keyword-only"
)
with tm.assert_produces_warning(FutureWarning, match=msg):
result = concat([df, df2], 0)
expected = DataFrame([[1, 2, 3], [4, 5, 6]], index=["a", "b"])
tm.assert_frame_equal(result, expected)
@pytest.mark.parametrize(
"data",
[
Series(data=[1, 2]),
DataFrame(
data={
"col1": [1, 2],
}
),
DataFrame(dtype=float),
Series(dtype=float),
],
)
def test_concat_drop_attrs(data):
# GH#41828
df1 = data.copy()
df1.attrs = {1: 1}
df2 = data.copy()
df2.attrs = {1: 2}
df = concat([df1, df2])
assert len(df.attrs) == 0
@pytest.mark.parametrize(
"data",
[
Series(data=[1, 2]),
DataFrame(
data={
"col1": [1, 2],
}
),
DataFrame(dtype=float),
Series(dtype=float),
],
)
def test_concat_retain_attrs(data):
# GH#41828
df1 = data.copy()
df1.attrs = {1: 1}
df2 = data.copy()
df2.attrs = {1: 1}
df = concat([df1, df2])
assert df.attrs[1] == 1
@td.skip_array_manager_invalid_test
@pytest.mark.parametrize("df_dtype", ["float64", "int64", "datetime64[ns]"])
@pytest.mark.parametrize("empty_dtype", [None, "float64", "object"])
def test_concat_ignore_emtpy_object_float(empty_dtype, df_dtype):
# https://github.com/pandas-dev/pandas/issues/45637
df = DataFrame({"foo": [1, 2], "bar": [1, 2]}, dtype=df_dtype)
empty = DataFrame(columns=["foo", "bar"], dtype=empty_dtype)
result = concat([empty, df])
expected = df
if df_dtype == "int64":
# TODO what exact behaviour do we want for integer eventually?
if empty_dtype == "float64":
expected = df.astype("float64")
else:
expected = df.astype("object")
tm.assert_frame_equal(result, expected)
@td.skip_array_manager_invalid_test
@pytest.mark.parametrize("df_dtype", ["float64", "int64", "datetime64[ns]"])
@pytest.mark.parametrize("empty_dtype", [None, "float64", "object"])
def test_concat_ignore_all_na_object_float(empty_dtype, df_dtype):
df = DataFrame({"foo": [1, 2], "bar": [1, 2]}, dtype=df_dtype)
empty = DataFrame({"foo": [np.nan], "bar": [np.nan]}, dtype=empty_dtype)
result = concat([empty, df], ignore_index=True)
if df_dtype == "int64":
# TODO what exact behaviour do we want for integer eventually?
if empty_dtype == "object":
df_dtype = "object"
else:
df_dtype = "float64"
expected = DataFrame({"foo": [None, 1, 2], "bar": [None, 1, 2]}, dtype=df_dtype)
tm.assert_frame_equal(result, expected)
@td.skip_array_manager_invalid_test
def test_concat_ignore_empty_from_reindex():
# https://github.com/pandas-dev/pandas/pull/43507#issuecomment-920375856
df1 = DataFrame({"a": [1], "b": [pd.Timestamp("2012-01-01")]})
df2 = DataFrame({"a": [2]})
result = concat([df1, df2.reindex(columns=df1.columns)], ignore_index=True)
expected = df1 = DataFrame({"a": [1, 2], "b": [pd.Timestamp("2012-01-01"), pd.NaT]})
tm.assert_frame_equal(result, expected)