laywerrobot/lib/python3.6/site-packages/pandas/tests/groupby/aggregate/test_aggregate.py
2020-08-27 21:55:39 +02:00

288 lines
9.3 KiB
Python

# -*- coding: utf-8 -*-
"""
test .agg behavior / note that .apply is tested generally in test_groupby.py
"""
import pytest
import numpy as np
import pandas as pd
from pandas import concat, DataFrame, Index, MultiIndex, Series
from pandas.core.groupby.groupby import Grouping, SpecificationError
from pandas.compat import OrderedDict
import pandas.util.testing as tm
def test_agg_regression1(tsframe):
grouped = tsframe.groupby([lambda x: x.year, lambda x: x.month])
result = grouped.agg(np.mean)
expected = grouped.mean()
tm.assert_frame_equal(result, expected)
def test_agg_must_agg(df):
grouped = df.groupby('A')['C']
msg = "Must produce aggregated value"
with tm.assert_raises_regex(Exception, msg):
grouped.agg(lambda x: x.describe())
with tm.assert_raises_regex(Exception, msg):
grouped.agg(lambda x: x.index[:2])
def test_agg_ser_multi_key(df):
# TODO(wesm): unused
ser = df.C # noqa
f = lambda x: x.sum()
results = df.C.groupby([df.A, df.B]).aggregate(f)
expected = df.groupby(['A', 'B']).sum()['C']
tm.assert_series_equal(results, expected)
def test_groupby_aggregation_mixed_dtype():
# GH 6212
expected = DataFrame({
'v1': [5, 5, 7, np.nan, 3, 3, 4, 1],
'v2': [55, 55, 77, np.nan, 33, 33, 44, 11]},
index=MultiIndex.from_tuples([(1, 95), (1, 99), (2, 95), (2, 99),
('big', 'damp'),
('blue', 'dry'),
('red', 'red'), ('red', 'wet')],
names=['by1', 'by2']))
df = DataFrame({
'v1': [1, 3, 5, 7, 8, 3, 5, np.nan, 4, 5, 7, 9],
'v2': [11, 33, 55, 77, 88, 33, 55, np.nan, 44, 55, 77, 99],
'by1': ["red", "blue", 1, 2, np.nan, "big", 1, 2, "red", 1, np.nan,
12],
'by2': ["wet", "dry", 99, 95, np.nan, "damp", 95, 99, "red", 99,
np.nan, np.nan]
})
g = df.groupby(['by1', 'by2'])
result = g[['v1', 'v2']].mean()
tm.assert_frame_equal(result, expected)
def test_agg_apply_corner(ts, tsframe):
# nothing to group, all NA
grouped = ts.groupby(ts * np.nan)
assert ts.dtype == np.float64
# groupby float64 values results in Float64Index
exp = Series([], dtype=np.float64,
index=pd.Index([], dtype=np.float64))
tm.assert_series_equal(grouped.sum(), exp)
tm.assert_series_equal(grouped.agg(np.sum), exp)
tm.assert_series_equal(grouped.apply(np.sum), exp,
check_index_type=False)
# DataFrame
grouped = tsframe.groupby(tsframe['A'] * np.nan)
exp_df = DataFrame(columns=tsframe.columns, dtype=float,
index=pd.Index([], dtype=np.float64))
tm.assert_frame_equal(grouped.sum(), exp_df, check_names=False)
tm.assert_frame_equal(grouped.agg(np.sum), exp_df, check_names=False)
tm.assert_frame_equal(grouped.apply(np.sum), exp_df.iloc[:, :0],
check_names=False)
def test_agg_grouping_is_list_tuple(ts):
df = tm.makeTimeDataFrame()
grouped = df.groupby(lambda x: x.year)
grouper = grouped.grouper.groupings[0].grouper
grouped.grouper.groupings[0] = Grouping(ts.index, list(grouper))
result = grouped.agg(np.mean)
expected = grouped.mean()
tm.assert_frame_equal(result, expected)
grouped.grouper.groupings[0] = Grouping(ts.index, tuple(grouper))
result = grouped.agg(np.mean)
expected = grouped.mean()
tm.assert_frame_equal(result, expected)
def test_agg_python_multiindex(mframe):
grouped = mframe.groupby(['A', 'B'])
result = grouped.agg(np.mean)
expected = grouped.mean()
tm.assert_frame_equal(result, expected)
@pytest.mark.parametrize('groupbyfunc', [
lambda x: x.weekday(),
[lambda x: x.month, lambda x: x.weekday()],
])
def test_aggregate_str_func(tsframe, groupbyfunc):
grouped = tsframe.groupby(groupbyfunc)
# single series
result = grouped['A'].agg('std')
expected = grouped['A'].std()
tm.assert_series_equal(result, expected)
# group frame by function name
result = grouped.aggregate('var')
expected = grouped.var()
tm.assert_frame_equal(result, expected)
# group frame by function dict
result = grouped.agg(OrderedDict([['A', 'var'],
['B', 'std'],
['C', 'mean'],
['D', 'sem']]))
expected = DataFrame(OrderedDict([['A', grouped['A'].var()],
['B', grouped['B'].std()],
['C', grouped['C'].mean()],
['D', grouped['D'].sem()]]))
tm.assert_frame_equal(result, expected)
def test_aggregate_item_by_item(df):
grouped = df.groupby('A')
aggfun = lambda ser: ser.size
result = grouped.agg(aggfun)
foo = (df.A == 'foo').sum()
bar = (df.A == 'bar').sum()
K = len(result.columns)
# GH5782
# odd comparisons can result here, so cast to make easy
exp = pd.Series(np.array([foo] * K), index=list('BCD'),
dtype=np.float64, name='foo')
tm.assert_series_equal(result.xs('foo'), exp)
exp = pd.Series(np.array([bar] * K), index=list('BCD'),
dtype=np.float64, name='bar')
tm.assert_almost_equal(result.xs('bar'), exp)
def aggfun(ser):
return ser.size
result = DataFrame().groupby(df.A).agg(aggfun)
assert isinstance(result, DataFrame)
assert len(result) == 0
def test_wrap_agg_out(three_group):
grouped = three_group.groupby(['A', 'B'])
def func(ser):
if ser.dtype == np.object:
raise TypeError
else:
return ser.sum()
result = grouped.aggregate(func)
exp_grouped = three_group.loc[:, three_group.columns != 'C']
expected = exp_grouped.groupby(['A', 'B']).aggregate(func)
tm.assert_frame_equal(result, expected)
def test_agg_multiple_functions_maintain_order(df):
# GH #610
funcs = [('mean', np.mean), ('max', np.max), ('min', np.min)]
result = df.groupby('A')['C'].agg(funcs)
exp_cols = Index(['mean', 'max', 'min'])
tm.assert_index_equal(result.columns, exp_cols)
def test_multiple_functions_tuples_and_non_tuples(df):
# #1359
funcs = [('foo', 'mean'), 'std']
ex_funcs = [('foo', 'mean'), ('std', 'std')]
result = df.groupby('A')['C'].agg(funcs)
expected = df.groupby('A')['C'].agg(ex_funcs)
tm.assert_frame_equal(result, expected)
result = df.groupby('A').agg(funcs)
expected = df.groupby('A').agg(ex_funcs)
tm.assert_frame_equal(result, expected)
def test_agg_multiple_functions_too_many_lambdas(df):
grouped = df.groupby('A')
funcs = ['mean', lambda x: x.mean(), lambda x: x.std()]
msg = 'Function names must be unique, found multiple named <lambda>'
with tm.assert_raises_regex(SpecificationError, msg):
grouped.agg(funcs)
def test_more_flexible_frame_multi_function(df):
grouped = df.groupby('A')
exmean = grouped.agg(OrderedDict([['C', np.mean], ['D', np.mean]]))
exstd = grouped.agg(OrderedDict([['C', np.std], ['D', np.std]]))
expected = concat([exmean, exstd], keys=['mean', 'std'], axis=1)
expected = expected.swaplevel(0, 1, axis=1).sort_index(level=0, axis=1)
d = OrderedDict([['C', [np.mean, np.std]], ['D', [np.mean, np.std]]])
result = grouped.aggregate(d)
tm.assert_frame_equal(result, expected)
# be careful
result = grouped.aggregate(OrderedDict([['C', np.mean],
['D', [np.mean, np.std]]]))
expected = grouped.aggregate(OrderedDict([['C', np.mean],
['D', [np.mean, np.std]]]))
tm.assert_frame_equal(result, expected)
def foo(x):
return np.mean(x)
def bar(x):
return np.std(x, ddof=1)
# this uses column selection & renaming
with tm.assert_produces_warning(FutureWarning, check_stacklevel=False):
d = OrderedDict([['C', np.mean],
['D', OrderedDict([['foo', np.mean],
['bar', np.std]])]])
result = grouped.aggregate(d)
d = OrderedDict([['C', [np.mean]], ['D', [foo, bar]]])
expected = grouped.aggregate(d)
tm.assert_frame_equal(result, expected)
def test_multi_function_flexible_mix(df):
# GH #1268
grouped = df.groupby('A')
# Expected
d = OrderedDict([['C', OrderedDict([['foo', 'mean'], ['bar', 'std']])],
['D', {'sum': 'sum'}]])
# this uses column selection & renaming
with tm.assert_produces_warning(FutureWarning, check_stacklevel=False):
expected = grouped.aggregate(d)
# Test 1
d = OrderedDict([['C', OrderedDict([['foo', 'mean'], ['bar', 'std']])],
['D', 'sum']])
# this uses column selection & renaming
with tm.assert_produces_warning(FutureWarning, check_stacklevel=False):
result = grouped.aggregate(d)
tm.assert_frame_equal(result, expected)
# Test 2
d = OrderedDict([['C', OrderedDict([['foo', 'mean'], ['bar', 'std']])],
['D', ['sum']]])
# this uses column selection & renaming
with tm.assert_produces_warning(FutureWarning, check_stacklevel=False):
result = grouped.aggregate(d)
tm.assert_frame_equal(result, expected)