projektAI/venv/Lib/site-packages/pandas/tests/window/moments/test_moments_consistency_expanding.py

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2021-06-06 22:13:05 +02:00
import numpy as np
import pytest
from pandas import DataFrame, Index, MultiIndex, Series, isna, notna
import pandas._testing as tm
def test_expanding_corr(series):
A = series.dropna()
B = (A + np.random.randn(len(A)))[:-5]
result = A.expanding().corr(B)
rolling_result = A.rolling(window=len(A), min_periods=1).corr(B)
tm.assert_almost_equal(rolling_result, result)
def test_expanding_count(series):
result = series.expanding(min_periods=0).count()
tm.assert_almost_equal(
result, series.rolling(window=len(series), min_periods=0).count()
)
def test_expanding_quantile(series):
result = series.expanding().quantile(0.5)
rolling_result = series.rolling(window=len(series), min_periods=1).quantile(0.5)
tm.assert_almost_equal(result, rolling_result)
def test_expanding_cov(series):
A = series
B = (A + np.random.randn(len(A)))[:-5]
result = A.expanding().cov(B)
rolling_result = A.rolling(window=len(A), min_periods=1).cov(B)
tm.assert_almost_equal(rolling_result, result)
def test_expanding_cov_pairwise(frame):
result = frame.expanding().cov()
rolling_result = frame.rolling(window=len(frame), min_periods=1).cov()
tm.assert_frame_equal(result, rolling_result)
def test_expanding_corr_pairwise(frame):
result = frame.expanding().corr()
rolling_result = frame.rolling(window=len(frame), min_periods=1).corr()
tm.assert_frame_equal(result, rolling_result)
@pytest.mark.parametrize(
"func,static_comp",
[("sum", np.sum), ("mean", np.mean), ("max", np.max), ("min", np.min)],
ids=["sum", "mean", "max", "min"],
)
def test_expanding_func(func, static_comp, frame_or_series):
data = frame_or_series(np.array(list(range(10)) + [np.nan] * 10))
result = getattr(data.expanding(min_periods=1, axis=0), func)()
assert isinstance(result, frame_or_series)
if frame_or_series is Series:
tm.assert_almost_equal(result[10], static_comp(data[:11]))
else:
tm.assert_series_equal(
result.iloc[10], static_comp(data[:11]), check_names=False
)
@pytest.mark.parametrize(
"func,static_comp",
[("sum", np.sum), ("mean", np.mean), ("max", np.max), ("min", np.min)],
ids=["sum", "mean", "max", "min"],
)
def test_expanding_min_periods(func, static_comp):
ser = Series(np.random.randn(50))
result = getattr(ser.expanding(min_periods=30, axis=0), func)()
assert result[:29].isna().all()
tm.assert_almost_equal(result.iloc[-1], static_comp(ser[:50]))
# min_periods is working correctly
result = getattr(ser.expanding(min_periods=15, axis=0), func)()
assert isna(result.iloc[13])
assert notna(result.iloc[14])
ser2 = Series(np.random.randn(20))
result = getattr(ser2.expanding(min_periods=5, axis=0), func)()
assert isna(result[3])
assert notna(result[4])
# min_periods=0
result0 = getattr(ser.expanding(min_periods=0, axis=0), func)()
result1 = getattr(ser.expanding(min_periods=1, axis=0), func)()
tm.assert_almost_equal(result0, result1)
result = getattr(ser.expanding(min_periods=1, axis=0), func)()
tm.assert_almost_equal(result.iloc[-1], static_comp(ser[:50]))
def test_expanding_apply(engine_and_raw, frame_or_series):
engine, raw = engine_and_raw
data = frame_or_series(np.array(list(range(10)) + [np.nan] * 10))
result = data.expanding(min_periods=1).apply(
lambda x: x.mean(), raw=raw, engine=engine
)
assert isinstance(result, frame_or_series)
if frame_or_series is Series:
tm.assert_almost_equal(result[9], np.mean(data[:11]))
else:
tm.assert_series_equal(result.iloc[9], np.mean(data[:11]), check_names=False)
def test_expanding_min_periods_apply(engine_and_raw):
engine, raw = engine_and_raw
ser = Series(np.random.randn(50))
result = ser.expanding(min_periods=30).apply(
lambda x: x.mean(), raw=raw, engine=engine
)
assert result[:29].isna().all()
tm.assert_almost_equal(result.iloc[-1], np.mean(ser[:50]))
# min_periods is working correctly
result = ser.expanding(min_periods=15).apply(
lambda x: x.mean(), raw=raw, engine=engine
)
assert isna(result.iloc[13])
assert notna(result.iloc[14])
ser2 = Series(np.random.randn(20))
result = ser2.expanding(min_periods=5).apply(
lambda x: x.mean(), raw=raw, engine=engine
)
assert isna(result[3])
assert notna(result[4])
# min_periods=0
result0 = ser.expanding(min_periods=0).apply(
lambda x: x.mean(), raw=raw, engine=engine
)
result1 = ser.expanding(min_periods=1).apply(
lambda x: x.mean(), raw=raw, engine=engine
)
tm.assert_almost_equal(result0, result1)
result = ser.expanding(min_periods=1).apply(
lambda x: x.mean(), raw=raw, engine=engine
)
tm.assert_almost_equal(result.iloc[-1], np.mean(ser[:50]))
@pytest.mark.parametrize("min_periods", [0, 1, 2, 3, 4])
@pytest.mark.parametrize("f", [lambda v: Series(v).sum(), np.nansum])
def test_expanding_apply_consistency_sum_nans(consistency_data, min_periods, f):
x, is_constant, no_nans = consistency_data
if f is np.nansum and min_periods == 0:
pass
else:
expanding_f_result = x.expanding(min_periods=min_periods).sum()
expanding_apply_f_result = x.expanding(min_periods=min_periods).apply(
func=f, raw=True
)
tm.assert_equal(expanding_f_result, expanding_apply_f_result)
@pytest.mark.parametrize("min_periods", [0, 1, 2, 3, 4])
@pytest.mark.parametrize("f", [lambda v: Series(v).sum(), np.nansum, np.sum])
def test_expanding_apply_consistency_sum_no_nans(consistency_data, min_periods, f):
x, is_constant, no_nans = consistency_data
if no_nans:
if f is np.nansum and min_periods == 0:
pass
else:
expanding_f_result = x.expanding(min_periods=min_periods).sum()
expanding_apply_f_result = x.expanding(min_periods=min_periods).apply(
func=f, raw=True
)
tm.assert_equal(expanding_f_result, expanding_apply_f_result)
@pytest.mark.parametrize("min_periods", [0, 1, 2, 3, 4])
@pytest.mark.parametrize("ddof", [0, 1])
def test_moments_consistency_var(consistency_data, min_periods, ddof):
x, is_constant, no_nans = consistency_data
mean_x = x.expanding(min_periods=min_periods).mean()
var_x = x.expanding(min_periods=min_periods).var(ddof=ddof)
assert not (var_x < 0).any().any()
if ddof == 0:
# check that biased var(x) == mean(x^2) - mean(x)^2
mean_x2 = (x * x).expanding(min_periods=min_periods).mean()
tm.assert_equal(var_x, mean_x2 - (mean_x * mean_x))
@pytest.mark.parametrize("min_periods", [0, 1, 2, 3, 4])
@pytest.mark.parametrize("ddof", [0, 1])
def test_moments_consistency_var_constant(consistency_data, min_periods, ddof):
x, is_constant, no_nans = consistency_data
if is_constant:
count_x = x.expanding(min_periods=min_periods).count()
var_x = x.expanding(min_periods=min_periods).var(ddof=ddof)
# check that variance of constant series is identically 0
assert not (var_x > 0).any().any()
expected = x * np.nan
expected[count_x >= max(min_periods, 1)] = 0.0
if ddof == 1:
expected[count_x < 2] = np.nan
tm.assert_equal(var_x, expected)
@pytest.mark.parametrize("min_periods", [0, 1, 2, 3, 4])
@pytest.mark.parametrize("ddof", [0, 1])
def test_expanding_consistency_std(consistency_data, min_periods, ddof):
x, is_constant, no_nans = consistency_data
var_x = x.expanding(min_periods=min_periods).var(ddof=ddof)
std_x = x.expanding(min_periods=min_periods).std(ddof=ddof)
assert not (var_x < 0).any().any()
assert not (std_x < 0).any().any()
# check that var(x) == std(x)^2
tm.assert_equal(var_x, std_x * std_x)
@pytest.mark.parametrize("min_periods", [0, 1, 2, 3, 4])
@pytest.mark.parametrize("ddof", [0, 1])
def test_expanding_consistency_cov(consistency_data, min_periods, ddof):
x, is_constant, no_nans = consistency_data
var_x = x.expanding(min_periods=min_periods).var(ddof=ddof)
assert not (var_x < 0).any().any()
cov_x_x = x.expanding(min_periods=min_periods).cov(x, ddof=ddof)
assert not (cov_x_x < 0).any().any()
# check that var(x) == cov(x, x)
tm.assert_equal(var_x, cov_x_x)
@pytest.mark.parametrize("min_periods", [0, 1, 2, 3, 4])
@pytest.mark.parametrize("ddof", [0, 1])
def test_expanding_consistency_series_cov_corr(consistency_data, min_periods, ddof):
x, is_constant, no_nans = consistency_data
if isinstance(x, Series):
var_x_plus_y = (x + x).expanding(min_periods=min_periods).var(ddof=ddof)
var_x = x.expanding(min_periods=min_periods).var(ddof=ddof)
var_y = x.expanding(min_periods=min_periods).var(ddof=ddof)
cov_x_y = x.expanding(min_periods=min_periods).cov(x, ddof=ddof)
# check that cov(x, y) == (var(x+y) - var(x) -
# var(y)) / 2
tm.assert_equal(cov_x_y, 0.5 * (var_x_plus_y - var_x - var_y))
# check that corr(x, y) == cov(x, y) / (std(x) *
# std(y))
corr_x_y = x.expanding(min_periods=min_periods).corr(x)
std_x = x.expanding(min_periods=min_periods).std(ddof=ddof)
std_y = x.expanding(min_periods=min_periods).std(ddof=ddof)
tm.assert_equal(corr_x_y, cov_x_y / (std_x * std_y))
if ddof == 0:
# check that biased cov(x, y) == mean(x*y) -
# mean(x)*mean(y)
mean_x = x.expanding(min_periods=min_periods).mean()
mean_y = x.expanding(min_periods=min_periods).mean()
mean_x_times_y = (x * x).expanding(min_periods=min_periods).mean()
tm.assert_equal(cov_x_y, mean_x_times_y - (mean_x * mean_y))
@pytest.mark.parametrize("min_periods", [0, 1, 2, 3, 4])
def test_expanding_consistency_mean(consistency_data, min_periods):
x, is_constant, no_nans = consistency_data
result = x.expanding(min_periods=min_periods).mean()
expected = (
x.expanding(min_periods=min_periods).sum()
/ x.expanding(min_periods=min_periods).count()
)
tm.assert_equal(result, expected.astype("float64"))
@pytest.mark.parametrize("min_periods", [0, 1, 2, 3, 4])
def test_expanding_consistency_constant(consistency_data, min_periods):
x, is_constant, no_nans = consistency_data
if is_constant:
count_x = x.expanding().count()
mean_x = x.expanding(min_periods=min_periods).mean()
# check that correlation of a series with itself is either 1 or NaN
corr_x_x = x.expanding(min_periods=min_periods).corr(x)
exp = x.max() if isinstance(x, Series) else x.max().max()
# check mean of constant series
expected = x * np.nan
expected[count_x >= max(min_periods, 1)] = exp
tm.assert_equal(mean_x, expected)
# check correlation of constant series with itself is NaN
expected[:] = np.nan
tm.assert_equal(corr_x_x, expected)
@pytest.mark.parametrize("min_periods", [0, 1, 2, 3, 4])
def test_expanding_consistency_var_debiasing_factors(consistency_data, min_periods):
x, is_constant, no_nans = consistency_data
# check variance debiasing factors
var_unbiased_x = x.expanding(min_periods=min_periods).var()
var_biased_x = x.expanding(min_periods=min_periods).var(ddof=0)
var_debiasing_factors_x = x.expanding().count() / (
x.expanding().count() - 1.0
).replace(0.0, np.nan)
tm.assert_equal(var_unbiased_x, var_biased_x * var_debiasing_factors_x)
@pytest.mark.parametrize(
"f",
[
lambda x: (x.expanding(min_periods=5).cov(x, pairwise=True)),
lambda x: (x.expanding(min_periods=5).corr(x, pairwise=True)),
],
)
def test_moment_functions_zero_length_pairwise(f):
df1 = DataFrame()
df2 = DataFrame(columns=Index(["a"], name="foo"), index=Index([], name="bar"))
df2["a"] = df2["a"].astype("float64")
df1_expected = DataFrame(
index=MultiIndex.from_product([df1.index, df1.columns]), columns=Index([])
)
df2_expected = DataFrame(
index=MultiIndex.from_product([df2.index, df2.columns], names=["bar", "foo"]),
columns=Index(["a"], name="foo"),
dtype="float64",
)
df1_result = f(df1)
tm.assert_frame_equal(df1_result, df1_expected)
df2_result = f(df2)
tm.assert_frame_equal(df2_result, df2_expected)
@pytest.mark.parametrize(
"f",
[
lambda x: x.expanding().count(),
lambda x: x.expanding(min_periods=5).cov(x, pairwise=False),
lambda x: x.expanding(min_periods=5).corr(x, pairwise=False),
lambda x: x.expanding(min_periods=5).max(),
lambda x: x.expanding(min_periods=5).min(),
lambda x: x.expanding(min_periods=5).sum(),
lambda x: x.expanding(min_periods=5).mean(),
lambda x: x.expanding(min_periods=5).std(),
lambda x: x.expanding(min_periods=5).var(),
lambda x: x.expanding(min_periods=5).skew(),
lambda x: x.expanding(min_periods=5).kurt(),
lambda x: x.expanding(min_periods=5).quantile(0.5),
lambda x: x.expanding(min_periods=5).median(),
lambda x: x.expanding(min_periods=5).apply(sum, raw=False),
lambda x: x.expanding(min_periods=5).apply(sum, raw=True),
],
)
def test_moment_functions_zero_length(f):
# GH 8056
s = Series(dtype=np.float64)
s_expected = s
df1 = DataFrame()
df1_expected = df1
df2 = DataFrame(columns=["a"])
df2["a"] = df2["a"].astype("float64")
df2_expected = df2
s_result = f(s)
tm.assert_series_equal(s_result, s_expected)
df1_result = f(df1)
tm.assert_frame_equal(df1_result, df1_expected)
df2_result = f(df2)
tm.assert_frame_equal(df2_result, df2_expected)
def test_expanding_apply_empty_series(engine_and_raw):
engine, raw = engine_and_raw
ser = Series([], dtype=np.float64)
tm.assert_series_equal(
ser, ser.expanding().apply(lambda x: x.mean(), raw=raw, engine=engine)
)
def test_expanding_apply_min_periods_0(engine_and_raw):
# GH 8080
engine, raw = engine_and_raw
s = Series([None, None, None])
result = s.expanding(min_periods=0).apply(lambda x: len(x), raw=raw, engine=engine)
expected = Series([1.0, 2.0, 3.0])
tm.assert_series_equal(result, expected)
def test_expanding_cov_diff_index():
# GH 7512
s1 = Series([1, 2, 3], index=[0, 1, 2])
s2 = Series([1, 3], index=[0, 2])
result = s1.expanding().cov(s2)
expected = Series([None, None, 2.0])
tm.assert_series_equal(result, expected)
s2a = Series([1, None, 3], index=[0, 1, 2])
result = s1.expanding().cov(s2a)
tm.assert_series_equal(result, expected)
s1 = Series([7, 8, 10], index=[0, 1, 3])
s2 = Series([7, 9, 10], index=[0, 2, 3])
result = s1.expanding().cov(s2)
expected = Series([None, None, None, 4.5])
tm.assert_series_equal(result, expected)
def test_expanding_corr_diff_index():
# GH 7512
s1 = Series([1, 2, 3], index=[0, 1, 2])
s2 = Series([1, 3], index=[0, 2])
result = s1.expanding().corr(s2)
expected = Series([None, None, 1.0])
tm.assert_series_equal(result, expected)
s2a = Series([1, None, 3], index=[0, 1, 2])
result = s1.expanding().corr(s2a)
tm.assert_series_equal(result, expected)
s1 = Series([7, 8, 10], index=[0, 1, 3])
s2 = Series([7, 9, 10], index=[0, 2, 3])
result = s1.expanding().corr(s2)
expected = Series([None, None, None, 1.0])
tm.assert_series_equal(result, expected)
def test_expanding_cov_pairwise_diff_length():
# GH 7512
df1 = DataFrame([[1, 5], [3, 2], [3, 9]], columns=Index(["A", "B"], name="foo"))
df1a = DataFrame(
[[1, 5], [3, 9]], index=[0, 2], columns=Index(["A", "B"], name="foo")
)
df2 = DataFrame(
[[5, 6], [None, None], [2, 1]], columns=Index(["X", "Y"], name="foo")
)
df2a = DataFrame(
[[5, 6], [2, 1]], index=[0, 2], columns=Index(["X", "Y"], name="foo")
)
# TODO: xref gh-15826
# .loc is not preserving the names
result1 = df1.expanding().cov(df2, pairwise=True).loc[2]
result2 = df1.expanding().cov(df2a, pairwise=True).loc[2]
result3 = df1a.expanding().cov(df2, pairwise=True).loc[2]
result4 = df1a.expanding().cov(df2a, pairwise=True).loc[2]
expected = DataFrame(
[[-3.0, -6.0], [-5.0, -10.0]],
columns=Index(["A", "B"], name="foo"),
index=Index(["X", "Y"], name="foo"),
)
tm.assert_frame_equal(result1, expected)
tm.assert_frame_equal(result2, expected)
tm.assert_frame_equal(result3, expected)
tm.assert_frame_equal(result4, expected)
def test_expanding_corr_pairwise_diff_length():
# GH 7512
df1 = DataFrame(
[[1, 2], [3, 2], [3, 4]], columns=["A", "B"], index=Index(range(3), name="bar")
)
df1a = DataFrame(
[[1, 2], [3, 4]], index=Index([0, 2], name="bar"), columns=["A", "B"]
)
df2 = DataFrame(
[[5, 6], [None, None], [2, 1]],
columns=["X", "Y"],
index=Index(range(3), name="bar"),
)
df2a = DataFrame(
[[5, 6], [2, 1]], index=Index([0, 2], name="bar"), columns=["X", "Y"]
)
result1 = df1.expanding().corr(df2, pairwise=True).loc[2]
result2 = df1.expanding().corr(df2a, pairwise=True).loc[2]
result3 = df1a.expanding().corr(df2, pairwise=True).loc[2]
result4 = df1a.expanding().corr(df2a, pairwise=True).loc[2]
expected = DataFrame(
[[-1.0, -1.0], [-1.0, -1.0]], columns=["A", "B"], index=Index(["X", "Y"])
)
tm.assert_frame_equal(result1, expected)
tm.assert_frame_equal(result2, expected)
tm.assert_frame_equal(result3, expected)
tm.assert_frame_equal(result4, expected)
def test_expanding_apply_args_kwargs(engine_and_raw):
def mean_w_arg(x, const):
return np.mean(x) + const
engine, raw = engine_and_raw
df = DataFrame(np.random.rand(20, 3))
expected = df.expanding().apply(np.mean, engine=engine, raw=raw) + 20.0
result = df.expanding().apply(mean_w_arg, engine=engine, raw=raw, args=(20,))
tm.assert_frame_equal(result, expected)
result = df.expanding().apply(mean_w_arg, raw=raw, kwargs={"const": 20})
tm.assert_frame_equal(result, expected)