aoc-2022/venv/Lib/site-packages/pandas/tests/frame/methods/test_interpolate.py

412 lines
14 KiB
Python

import numpy as np
import pytest
import pandas.util._test_decorators as td
from pandas import (
DataFrame,
Series,
date_range,
)
import pandas._testing as tm
class TestDataFrameInterpolate:
def test_interpolate_inplace(self, frame_or_series, using_array_manager, request):
# GH#44749
if using_array_manager and frame_or_series is DataFrame:
mark = pytest.mark.xfail(reason=".values-based in-place check is invalid")
request.node.add_marker(mark)
obj = frame_or_series([1, np.nan, 2])
orig = obj.values
obj.interpolate(inplace=True)
expected = frame_or_series([1, 1.5, 2])
tm.assert_equal(obj, expected)
# check we operated *actually* inplace
assert np.shares_memory(orig, obj.values)
assert orig.squeeze()[1] == 1.5
def test_interp_basic(self):
df = DataFrame(
{
"A": [1, 2, np.nan, 4],
"B": [1, 4, 9, np.nan],
"C": [1, 2, 3, 5],
"D": list("abcd"),
}
)
expected = DataFrame(
{
"A": [1.0, 2.0, 3.0, 4.0],
"B": [1.0, 4.0, 9.0, 9.0],
"C": [1, 2, 3, 5],
"D": list("abcd"),
}
)
result = df.interpolate()
tm.assert_frame_equal(result, expected)
# check we didn't operate inplace GH#45791
cvalues = df["C"]._values
dvalues = df["D"].values
assert not np.shares_memory(cvalues, result["C"]._values)
assert not np.shares_memory(dvalues, result["D"]._values)
res = df.interpolate(inplace=True)
assert res is None
tm.assert_frame_equal(df, expected)
# check we DID operate inplace
assert np.shares_memory(df["C"]._values, cvalues)
assert np.shares_memory(df["D"]._values, dvalues)
def test_interp_basic_with_non_range_index(self):
df = DataFrame(
{
"A": [1, 2, np.nan, 4],
"B": [1, 4, 9, np.nan],
"C": [1, 2, 3, 5],
"D": list("abcd"),
}
)
expected = DataFrame(
{
"A": [1.0, 2.0, 3.0, 4.0],
"B": [1.0, 4.0, 9.0, 9.0],
"C": [1, 2, 3, 5],
"D": list("abcd"),
}
)
result = df.set_index("C").interpolate()
expected = df.set_index("C")
expected.loc[3, "A"] = 3
expected.loc[5, "B"] = 9
tm.assert_frame_equal(result, expected)
def test_interp_empty(self):
# https://github.com/pandas-dev/pandas/issues/35598
df = DataFrame()
result = df.interpolate()
assert result is not df
expected = df
tm.assert_frame_equal(result, expected)
def test_interp_bad_method(self):
df = DataFrame(
{
"A": [1, 2, np.nan, 4],
"B": [1, 4, 9, np.nan],
"C": [1, 2, 3, 5],
"D": list("abcd"),
}
)
msg = (
r"method must be one of \['linear', 'time', 'index', 'values', "
r"'nearest', 'zero', 'slinear', 'quadratic', 'cubic', "
r"'barycentric', 'krogh', 'spline', 'polynomial', "
r"'from_derivatives', 'piecewise_polynomial', 'pchip', 'akima', "
r"'cubicspline'\]. Got 'not_a_method' instead."
)
with pytest.raises(ValueError, match=msg):
df.interpolate(method="not_a_method")
def test_interp_combo(self):
df = DataFrame(
{
"A": [1.0, 2.0, np.nan, 4.0],
"B": [1, 4, 9, np.nan],
"C": [1, 2, 3, 5],
"D": list("abcd"),
}
)
result = df["A"].interpolate()
expected = Series([1.0, 2.0, 3.0, 4.0], name="A")
tm.assert_series_equal(result, expected)
result = df["A"].interpolate(downcast="infer")
expected = Series([1, 2, 3, 4], name="A")
tm.assert_series_equal(result, expected)
def test_interp_nan_idx(self):
df = DataFrame({"A": [1, 2, np.nan, 4], "B": [np.nan, 2, 3, 4]})
df = df.set_index("A")
msg = (
"Interpolation with NaNs in the index has not been implemented. "
"Try filling those NaNs before interpolating."
)
with pytest.raises(NotImplementedError, match=msg):
df.interpolate(method="values")
@td.skip_if_no_scipy
def test_interp_various(self):
df = DataFrame(
{"A": [1, 2, np.nan, 4, 5, np.nan, 7], "C": [1, 2, 3, 5, 8, 13, 21]}
)
df = df.set_index("C")
expected = df.copy()
result = df.interpolate(method="polynomial", order=1)
expected.loc[3, "A"] = 2.66666667
expected.loc[13, "A"] = 5.76923076
tm.assert_frame_equal(result, expected)
result = df.interpolate(method="cubic")
# GH #15662.
expected.loc[3, "A"] = 2.81547781
expected.loc[13, "A"] = 5.52964175
tm.assert_frame_equal(result, expected)
result = df.interpolate(method="nearest")
expected.loc[3, "A"] = 2
expected.loc[13, "A"] = 5
tm.assert_frame_equal(result, expected, check_dtype=False)
result = df.interpolate(method="quadratic")
expected.loc[3, "A"] = 2.82150771
expected.loc[13, "A"] = 6.12648668
tm.assert_frame_equal(result, expected)
result = df.interpolate(method="slinear")
expected.loc[3, "A"] = 2.66666667
expected.loc[13, "A"] = 5.76923077
tm.assert_frame_equal(result, expected)
result = df.interpolate(method="zero")
expected.loc[3, "A"] = 2.0
expected.loc[13, "A"] = 5
tm.assert_frame_equal(result, expected, check_dtype=False)
@td.skip_if_no_scipy
def test_interp_alt_scipy(self):
df = DataFrame(
{"A": [1, 2, np.nan, 4, 5, np.nan, 7], "C": [1, 2, 3, 5, 8, 13, 21]}
)
result = df.interpolate(method="barycentric")
expected = df.copy()
expected.loc[2, "A"] = 3
expected.loc[5, "A"] = 6
tm.assert_frame_equal(result, expected)
result = df.interpolate(method="barycentric", downcast="infer")
tm.assert_frame_equal(result, expected.astype(np.int64))
result = df.interpolate(method="krogh")
expectedk = df.copy()
expectedk["A"] = expected["A"]
tm.assert_frame_equal(result, expectedk)
result = df.interpolate(method="pchip")
expected.loc[2, "A"] = 3
expected.loc[5, "A"] = 6.0
tm.assert_frame_equal(result, expected)
def test_interp_rowwise(self):
df = DataFrame(
{
0: [1, 2, np.nan, 4],
1: [2, 3, 4, np.nan],
2: [np.nan, 4, 5, 6],
3: [4, np.nan, 6, 7],
4: [1, 2, 3, 4],
}
)
result = df.interpolate(axis=1)
expected = df.copy()
expected.loc[3, 1] = 5
expected.loc[0, 2] = 3
expected.loc[1, 3] = 3
expected[4] = expected[4].astype(np.float64)
tm.assert_frame_equal(result, expected)
result = df.interpolate(axis=1, method="values")
tm.assert_frame_equal(result, expected)
result = df.interpolate(axis=0)
expected = df.interpolate()
tm.assert_frame_equal(result, expected)
@pytest.mark.parametrize(
"axis_name, axis_number",
[
pytest.param("rows", 0, id="rows_0"),
pytest.param("index", 0, id="index_0"),
pytest.param("columns", 1, id="columns_1"),
],
)
def test_interp_axis_names(self, axis_name, axis_number):
# GH 29132: test axis names
data = {0: [0, np.nan, 6], 1: [1, np.nan, 7], 2: [2, 5, 8]}
df = DataFrame(data, dtype=np.float64)
result = df.interpolate(axis=axis_name, method="linear")
expected = df.interpolate(axis=axis_number, method="linear")
tm.assert_frame_equal(result, expected)
def test_rowwise_alt(self):
df = DataFrame(
{
0: [0, 0.5, 1.0, np.nan, 4, 8, np.nan, np.nan, 64],
1: [1, 2, 3, 4, 3, 2, 1, 0, -1],
}
)
df.interpolate(axis=0)
# TODO: assert something?
@pytest.mark.parametrize(
"check_scipy", [False, pytest.param(True, marks=td.skip_if_no_scipy)]
)
def test_interp_leading_nans(self, check_scipy):
df = DataFrame(
{"A": [np.nan, np.nan, 0.5, 0.25, 0], "B": [np.nan, -3, -3.5, np.nan, -4]}
)
result = df.interpolate()
expected = df.copy()
expected.loc[3, "B"] = -3.75
tm.assert_frame_equal(result, expected)
if check_scipy:
result = df.interpolate(method="polynomial", order=1)
tm.assert_frame_equal(result, expected)
def test_interp_raise_on_only_mixed(self, axis):
df = DataFrame(
{
"A": [1, 2, np.nan, 4],
"B": ["a", "b", "c", "d"],
"C": [np.nan, 2, 5, 7],
"D": [np.nan, np.nan, 9, 9],
"E": [1, 2, 3, 4],
}
)
msg = (
"Cannot interpolate with all object-dtype columns "
"in the DataFrame. Try setting at least one "
"column to a numeric dtype."
)
with pytest.raises(TypeError, match=msg):
df.astype("object").interpolate(axis=axis)
def test_interp_raise_on_all_object_dtype(self):
# GH 22985
df = DataFrame({"A": [1, 2, 3], "B": [4, 5, 6]}, dtype="object")
msg = (
"Cannot interpolate with all object-dtype columns "
"in the DataFrame. Try setting at least one "
"column to a numeric dtype."
)
with pytest.raises(TypeError, match=msg):
df.interpolate()
def test_interp_inplace(self, using_copy_on_write):
# TODO(CoW) inplace keyword (it is still mutating the parent)
if using_copy_on_write:
pytest.skip("CoW: inplace keyword not yet handled")
df = DataFrame({"a": [1.0, 2.0, np.nan, 4.0]})
expected = DataFrame({"a": [1.0, 2.0, 3.0, 4.0]})
result = df.copy()
return_value = result["a"].interpolate(inplace=True)
assert return_value is None
tm.assert_frame_equal(result, expected)
result = df.copy()
return_value = result["a"].interpolate(inplace=True, downcast="infer")
assert return_value is None
tm.assert_frame_equal(result, expected.astype("int64"))
def test_interp_inplace_row(self):
# GH 10395
result = DataFrame(
{"a": [1.0, 2.0, 3.0, 4.0], "b": [np.nan, 2.0, 3.0, 4.0], "c": [3, 2, 2, 2]}
)
expected = result.interpolate(method="linear", axis=1, inplace=False)
return_value = result.interpolate(method="linear", axis=1, inplace=True)
assert return_value is None
tm.assert_frame_equal(result, expected)
def test_interp_ignore_all_good(self):
# GH
df = DataFrame(
{
"A": [1, 2, np.nan, 4],
"B": [1, 2, 3, 4],
"C": [1.0, 2.0, np.nan, 4.0],
"D": [1.0, 2.0, 3.0, 4.0],
}
)
expected = DataFrame(
{
"A": np.array([1, 2, 3, 4], dtype="float64"),
"B": np.array([1, 2, 3, 4], dtype="int64"),
"C": np.array([1.0, 2.0, 3, 4.0], dtype="float64"),
"D": np.array([1.0, 2.0, 3.0, 4.0], dtype="float64"),
}
)
result = df.interpolate(downcast=None)
tm.assert_frame_equal(result, expected)
# all good
result = df[["B", "D"]].interpolate(downcast=None)
tm.assert_frame_equal(result, df[["B", "D"]])
def test_interp_time_inplace_axis(self):
# GH 9687
periods = 5
idx = date_range(start="2014-01-01", periods=periods)
data = np.random.rand(periods, periods)
data[data < 0.5] = np.nan
expected = DataFrame(index=idx, columns=idx, data=data)
result = expected.interpolate(axis=0, method="time")
return_value = expected.interpolate(axis=0, method="time", inplace=True)
assert return_value is None
tm.assert_frame_equal(result, expected)
@pytest.mark.parametrize("axis_name, axis_number", [("index", 0), ("columns", 1)])
def test_interp_string_axis(self, axis_name, axis_number):
# https://github.com/pandas-dev/pandas/issues/25190
x = np.linspace(0, 100, 1000)
y = np.sin(x)
df = DataFrame(
data=np.tile(y, (10, 1)), index=np.arange(10), columns=x
).reindex(columns=x * 1.005)
result = df.interpolate(method="linear", axis=axis_name)
expected = df.interpolate(method="linear", axis=axis_number)
tm.assert_frame_equal(result, expected)
@pytest.mark.parametrize("method", ["ffill", "bfill", "pad"])
def test_interp_fillna_methods(self, request, axis, method, using_array_manager):
# GH 12918
if using_array_manager and (axis == 1 or axis == "columns"):
# TODO(ArrayManager) support axis=1
td.mark_array_manager_not_yet_implemented(request)
df = DataFrame(
{
"A": [1.0, 2.0, 3.0, 4.0, np.nan, 5.0],
"B": [2.0, 4.0, 6.0, np.nan, 8.0, 10.0],
"C": [3.0, 6.0, 9.0, np.nan, np.nan, 30.0],
}
)
expected = df.fillna(axis=axis, method=method)
result = df.interpolate(method=method, axis=axis)
tm.assert_frame_equal(result, expected)
def test_interpolate_pos_args_deprecation(self):
# https://github.com/pandas-dev/pandas/issues/41485
df = DataFrame({"a": [1, 2, 3]})
msg = (
r"In a future version of pandas all arguments of DataFrame.interpolate "
r"except for the argument 'method' will be keyword-only"
)
with tm.assert_produces_warning(FutureWarning, match=msg):
result = df.interpolate("pad", 0)
expected = DataFrame({"a": [1, 2, 3]})
tm.assert_frame_equal(result, expected)