Files
pytorch-ts/pts/feature/utils.py
T
Dr. Kashif Rasul 032f32faf0 black
2019-12-21 14:59:11 +01:00

52 lines
1.4 KiB
Python

import re
from typing import Tuple
from functools import lru_cache
def get_granularity(freq_str: str) -> Tuple[int, str]:
"""
Splits a frequency string such as "7D" into the multiple 7 and the base
granularity "D".
Parameters
----------
freq_str
Frequency string of the form [multiple][granularity] such as "12H", "5min", "1D" etc.
"""
freq_regex = r"\s*((\d+)?)\s*([^\d]\w*)"
m = re.match(freq_regex, freq_str)
assert m is not None, "Cannot parse frequency string: %s" % freq_str
groups = m.groups()
multiple = int(groups[1]) if groups[1] is not None else 1
granularity = groups[2]
return multiple, granularity
@lru_cache()
def get_seasonality(freq: str) -> int:
"""
Returns the default seasonality for a given freq str. E.g. for
2H -> 12
"""
match = re.match(r"(\d*)(\w+)", freq)
assert match, "Cannot match freq regex"
mult, base_freq = match.groups()
multiple = int(mult) if mult else 1
seasonalities = {"H": 24, "D": 1, "W": 1, "M": 12, "B": 5}
if base_freq in seasonalities:
seasonality = seasonalities[base_freq]
else:
seasonality = 1
if seasonality % multiple != 0:
# logging.warning(
# f"multiple {multiple} does not divide base "
# f"seasonality {seasonality}."
# f"Falling back to seasonality 1"
# )
return 1
return seasonality // multiple