def encode_with_label(self, X: pd.Series, y: pd.Series) -> pd.Series:
""" Encode categorical features with its percentage of positive samples"""
X, y = make_series(X), make_series(y)
pct_pos = y.groupby(X).mean()
# save the mapping for transform()
self.discrete_encoding[X.name] = pct_pos
return X.map(pct_pos)
def test_latest():
times = 7
max_lag = 4
series_list = []
for lag in range(max_lag + 1):
values = np.ones((times - lag, )) * lag
series_list.append(make_series(values, range(times - lag), lag))
expected = make_series([4, 4, 4, 3, 2, 1, 0], range(times))
assert np.allclose(expected, merge.latest(series_list))
def test_earliest():
times = 7
max_lag = 4
series_list = []
for lag in range(max_lag + 1):
values = np.ones((times - (max_lag - lag), )) * lag
series_list.append(
make_series(values, range(times - (max_lag - lag)), lag))
expected = make_series([0, 0, 0, 1, 2, 3, 4], range(times))
assert np.allclose(expected, merge.earliest(series_list))
def test_diff_linear_noninc():
expected_output_list = [
make_series(np.zeros(TIMES), range(TIMES), 0),
make_series(
np.concatenate([
np.linspace(0, TIMES - 3, TIMES - 2), [4.6666666666666661] * 2
]), range(TIMES), 1),
make_series(
np.concatenate([np.linspace(1, TIMES - 3, TIMES - 3), [5.0] * 3]),
range(TIMES), 2),
]
output = fill.diff_linear(INPUT_LIST)
for o, eo in zip(output, expected_output_list):
assert np.allclose(o, eo)
def is_monotonic(i, strict=True, ignore_na=True) -> bool:
""" Check if an iterable is monotonic """
i = make_series(i)
diff = i.diff()[1:]
if ignore_na:
diff = diff[diff.notnull()]
sign = diff > 0 if strict else diff >= 0
if sign.sum() == 0 or (~sign).sum() == 0:
return True
return False
def test_diff_mean_noninc():
"""
Check if the non incremental version works fine
"""
expected_output_list = [
make_series(np.zeros(TIMES), range(TIMES), 0),
make_series(
np.concatenate([np.linspace(0, TIMES - 3, TIMES - 2), [3.5] * 2]),
range(TIMES), 1),
make_series(
np.concatenate([np.linspace(1, TIMES - 3, TIMES - 3), [4.0] * 3]),
range(TIMES), 2),
]
output = fill.diff_mean(INPUT_LIST)
for o, eo in zip(output, expected_output_list):
assert np.allclose(o, eo)
def test_diff_mean_inc():
"""
Check for the incremental version
"""
expected_output_list = [
make_series(np.zeros(TIMES), range(TIMES), 0),
make_series(
np.concatenate([np.linspace(0, TIMES - 3, TIMES - 2), [3.5] * 2]),
range(TIMES), 1),
make_series(
np.concatenate(
[np.linspace(1, TIMES - 3, TIMES - 3), [8, 4.5, 4.5]]),
range(TIMES), 2),
]
output = fill.diff_mean(INPUT_LIST, inc=True)
for o, eo in zip(output, expected_output_list):
assert np.allclose(o, eo)
def test_mixer():
"""
Test for mixer
"""
# noop defaults to uniform weights
bias_fn = update.noop
main_fn = partial(update.pick, index=2)
mix_fn = update.create_mixer([main_fn, bias_fn], [0.3, 0.7])
losses = [
make_series(np.random.rand(10),
range(10),
extra_attrs={"model": model}) for model in MODELS
]
weights = mix_fn(losses)
expected_weights = make_weights([0.14, 0.14, 0.44, 0.14, 0.14], MODELS)
assert np.allclose(expected_weights, weights)
def _fit(self, X, y, **fit_parmas):
""" Fit a single feature and return the cutoff points"""
if not is_numeric_dtype(X) and X.name not in self.categorical_cols:
raise ValueError(
'Column {} is not numeric and not in categorical_cols.'.format(
X.name))
y = force_zero_one(y)
X, y = make_series(X), make_series(y)
# if X is discrete, encode with positive ratio in y
if X.name in self.categorical_cols:
# the categorical columns will remain unchanged if
# we turn off bin_cat_cols
if not self.bin_cat_cols:
return None
X = self.encode_with_label(X, y)
# the number of bins is the number of cutoff points minus 1
n_bins = X.nunique() - 1
# if the number of bins is already smaller than `n_bins`
# then we'll leave this column as it is
if n_bins < self.max_bin:
return None
# speed up the process with prebinning
if self.prebin and n_bins > self.prebin:
X, _ = equal_frequency_binning(X, n=self.prebin, encode=False)
# X = make_series(X)
# convert to mapping
mapping = y.groupby(X).apply(list).to_dict()
# set the overall expected ratio
if len(mapping) == 0:
return [-np.inf]
self.expected_ratio = sum(sum(v) for v in mapping.values()) / sum(
len(v) for v in mapping.values())
# if the expected_ratio is 0 or 1 there should be only 1 group and
# any not-null value will be encoded into 1
if self.expected_ratio == 0 or self.expected_ratio == 1:
return [-np.inf]
n_bins = len(mapping) - 1
# merge bins based on chi square
while n_bins > self.max_bin:
mapping = self.merge_chisquare(mapping)
n_bins = len(mapping) - 1
# merge bins to create mixed label in every bin
if self.force_mix_label and n_bins > 1:
is_pure = False
while not is_pure:
mapping, is_pure = self.merge_purity(mapping)
# merge bins to keep bins to be monotonic
if self.force_monotonic:
while len(mapping) - 1 > 2 and not self.is_monotonic_post_bin(
mapping):
mapping = self.merge_chisquare(mapping)
# clean up the cache
self._chisquare_cache = dict()
return mapping.keys()
import xarray as xr
import numpy as np
from ledge import fill
from utils import make_series
TIMES = 10
INPUT_LIST = [
make_series(np.zeros(TIMES), range(TIMES), 0),
make_series(np.linspace(0, TIMES - 3, TIMES - 2), range(TIMES - 2), 1),
make_series(np.linspace(1, TIMES - 3, TIMES - 3), range(TIMES - 3), 2)
]
def test_diff_mean_noninc():
"""
Check if the non incremental version works fine
"""
expected_output_list = [
make_series(np.zeros(TIMES), range(TIMES), 0),
make_series(
np.concatenate([np.linspace(0, TIMES - 3, TIMES - 2), [3.5] * 2]),
range(TIMES), 1),
make_series(
np.concatenate([np.linspace(1, TIMES - 3, TIMES - 3), [4.0] * 3]),
range(TIMES), 2),
]
output = fill.diff_mean(INPUT_LIST)
for o, eo in zip(output, expected_output_list):
