File size: 3,743 Bytes
62a2f1c |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 |
from typing import List
import numpy as np
import pandas as pd
from pandas.tseries import offsets
from pandas.tseries.frequencies import to_offset
class TimeFeature:
def __init__(self):
pass
def __call__(self, index: pd.DatetimeIndex) -> np.ndarray:
pass
def __repr__(self):
return self.__class__.__name__ + "()"
class SecondOfMinute(TimeFeature):
"""Minute of hour encoded as value between [-0.5, 0.5]"""
def __call__(self, index: pd.DatetimeIndex) -> np.ndarray:
return index.second / 59.0 - 0.5
class MinuteOfHour(TimeFeature):
"""Minute of hour encoded as value between [-0.5, 0.5]"""
def __call__(self, index: pd.DatetimeIndex) -> np.ndarray:
return index.minute / 59.0 - 0.5
class HourOfDay(TimeFeature):
"""Hour of day encoded as value between [-0.5, 0.5]"""
def __call__(self, index: pd.DatetimeIndex) -> np.ndarray:
return index.hour / 23.0 - 0.5
class DayOfWeek(TimeFeature):
"""Hour of day encoded as value between [-0.5, 0.5]"""
def __call__(self, index: pd.DatetimeIndex) -> np.ndarray:
return index.dayofweek / 6.0 - 0.5
class DayOfMonth(TimeFeature):
"""Day of month encoded as value between [-0.5, 0.5]"""
def __call__(self, index: pd.DatetimeIndex) -> np.ndarray:
return (index.day - 1) / 30.0 - 0.5
class DayOfYear(TimeFeature):
"""Day of year encoded as value between [-0.5, 0.5]"""
def __call__(self, index: pd.DatetimeIndex) -> np.ndarray:
return (index.dayofyear - 1) / 365.0 - 0.5
class MonthOfYear(TimeFeature):
"""Month of year encoded as value between [-0.5, 0.5]"""
def __call__(self, index: pd.DatetimeIndex) -> np.ndarray:
return (index.month - 1) / 11.0 - 0.5
class WeekOfYear(TimeFeature):
"""Week of year encoded as value between [-0.5, 0.5]"""
def __call__(self, index: pd.DatetimeIndex) -> np.ndarray:
return (index.isocalendar().week - 1) / 52.0 - 0.5
def time_features_from_frequency_str(freq_str: str) -> List[TimeFeature]:
"""
Returns a list of time features that will be appropriate for the given frequency string.
Parameters
----------
freq_str
Frequency string of the form [multiple][granularity] such as "12H", "5min", "1D" etc.
"""
features_by_offsets = {
offsets.YearEnd: [],
offsets.QuarterEnd: [MonthOfYear],
offsets.MonthEnd: [MonthOfYear],
offsets.Week: [DayOfMonth, WeekOfYear],
offsets.Day: [DayOfWeek, DayOfMonth, DayOfYear],
offsets.BusinessDay: [DayOfWeek, DayOfMonth, DayOfYear],
offsets.Hour: [HourOfDay, DayOfWeek, DayOfMonth, DayOfYear],
offsets.Minute: [
MinuteOfHour,
HourOfDay,
DayOfWeek,
DayOfMonth,
DayOfYear,
],
offsets.Second: [
SecondOfMinute,
MinuteOfHour,
HourOfDay,
DayOfWeek,
DayOfMonth,
DayOfYear,
],
}
offset = to_offset(freq_str)
for offset_type, feature_classes in features_by_offsets.items():
if isinstance(offset, offset_type):
return [cls() for cls in feature_classes]
supported_freq_msg = f"""
Unsupported frequency {freq_str}
The following frequencies are supported:
Y - yearly
alias: A
M - monthly
W - weekly
D - daily
B - business days
H - hourly
T - minutely
alias: min
S - secondly
"""
raise RuntimeError(supported_freq_msg)
def time_features(dates, freq='h'):
return np.vstack([feat(dates) for feat in time_features_from_frequency_str(freq)])
|