Files
catalyst/catalyst/exchange/utils/datetime_utils.py
T

363 lines
7.9 KiB
Python

import calendar
import math
import re
from datetime import datetime, timedelta, date
import pandas as pd
import pytz
from catalyst.exchange.exchange_errors import InvalidHistoryFrequencyError, \
InvalidHistoryFrequencyAlias
def get_date_from_ms(ms):
"""
The date from the number of miliseconds from the epoch.
Parameters
----------
ms: int
Returns
-------
datetime
"""
return datetime.fromtimestamp(ms / 1000.0)
def get_seconds_from_date(date):
"""
The number of seconds from the epoch.
Parameters
----------
date: datetime
Returns
-------
int
"""
epoch = datetime.utcfromtimestamp(0)
epoch = epoch.replace(tzinfo=pytz.UTC)
return int((date - epoch).total_seconds())
def get_delta(periods, data_frequency):
"""
Get a time delta based on the specified data frequency.
Parameters
----------
periods: int
data_frequency: str
Returns
-------
timedelta
"""
return timedelta(minutes=periods) \
if data_frequency == 'minute' else timedelta(days=periods)
def get_periods_range(freq, start_dt=None, end_dt=None, periods=None):
"""
Get a date range for the specified parameters.
Parameters
----------
start_dt: datetime
end_dt: datetime
freq: str
Returns
-------
DateTimeIndex
"""
if freq == 'minute':
freq = 'T'
elif freq == 'daily':
freq = 'D'
if start_dt is not None and end_dt is not None and periods is None:
return pd.date_range(start_dt, end_dt, freq=freq)
elif periods is not None and (start_dt is not None or end_dt is not None):
_, unit_periods, unit, _ = get_frequency(freq)
adj_periods = periods * unit_periods
# TODO: standardize time aliases to avoid any mapping
unit = 'd' if unit == 'D' else 'h' if unit == 'H' else 'm'
delta = pd.Timedelta(adj_periods, unit)
if start_dt is not None:
return pd.date_range(
start=start_dt,
end=start_dt + delta,
freq=freq,
closed='left',
)
else:
return pd.date_range(
start=end_dt - delta,
end=end_dt,
freq=freq,
)
else:
raise ValueError(
'Choose only two parameters between start_dt, end_dt '
'and periods.'
)
def get_periods(start_dt, end_dt, freq):
"""
The number of periods in the specified range.
Parameters
----------
start_dt: datetime
end_dt: datetime
freq: str
Returns
-------
int
"""
return len(get_periods_range(start_dt=start_dt, end_dt=end_dt, freq=freq))
def get_start_dt(end_dt, bar_count, data_frequency, include_first=True):
"""
The start date based on specified end date and data frequency.
Parameters
----------
end_dt: datetime
bar_count: int
data_frequency: str
include_first
Returns
-------
datetime
"""
periods = bar_count
if periods > 1:
delta = get_delta(periods, data_frequency)
start_dt = end_dt - delta
if not include_first:
start_dt += get_delta(1, data_frequency)
else:
start_dt = end_dt
return start_dt
def get_period_label(dt, data_frequency):
"""
The period label for the specified date and frequency.
Parameters
----------
dt: datetime
data_frequency: str
Returns
-------
str
"""
if data_frequency == 'minute':
return '{}-{:02d}'.format(dt.year, dt.month)
else:
return '{}'.format(dt.year)
def get_month_start_end(dt, first_day=None, last_day=None):
"""
The first and last day of the month for the specified date.
Parameters
----------
dt: datetime
first_day: datetime
last_day: datetime
Returns
-------
datetime, datetime
"""
month_range = calendar.monthrange(dt.year, dt.month)
if first_day:
month_start = first_day
else:
month_start = pd.to_datetime(datetime(
dt.year, dt.month, 1, 0, 0, 0, 0
), utc=True)
if last_day:
month_end = last_day
else:
month_end = pd.to_datetime(datetime(
dt.year, dt.month, month_range[1], 23, 59, 0, 0
), utc=True)
if month_end > pd.Timestamp.utcnow():
month_end = pd.Timestamp.utcnow().floor('1D')
return month_start, month_end
def get_year_start_end(dt, first_day=None, last_day=None):
"""
The first and last day of the year for the specified date.
Parameters
----------
dt: datetime
first_day: datetime
last_day: datetime
Returns
-------
datetime, datetime
"""
year_start = first_day if first_day \
else pd.to_datetime(date(dt.year, 1, 1), utc=True)
year_end = last_day if last_day \
else pd.to_datetime(date(dt.year, 12, 31), utc=True)
if year_end > pd.Timestamp.utcnow():
year_end = pd.Timestamp.utcnow().floor('1D')
return year_start, year_end
def get_frequency(freq, data_frequency=None, supported_freqs=['D', 'H', 'T']):
"""
Takes an arbitrary candle size (e.g. 15T) and converts to the lowest
common denominator supported by the data bundles (e.g. 1T). The data
bundles only support 1T and 1D frequencies. If another frequency
is requested, Catalyst must request the underlying data and resample.
Notes
-----
We're trying to use Pandas convention for frequency aliases.
Parameters
----------
freq: str
data_frequency: str
Returns
-------
str, int, str, str
"""
if data_frequency is None:
data_frequency = 'daily' if freq.upper().endswith('D') else 'minute'
if freq == 'minute':
unit = 'T'
candle_size = 1
elif freq == 'daily':
unit = 'D'
candle_size = 1
else:
freq_match = re.match(r'([0-9].*)?(m|M|d|D|h|H|T)', freq, re.M | re.I)
if freq_match:
candle_size = int(freq_match.group(1)) if freq_match.group(1) \
else 1
unit = freq_match.group(2)
else:
raise InvalidHistoryFrequencyError(frequency=freq)
# TODO: some exchanges support H and W frequencies but not bundles
# Find a way to pass-through these parameters to exchanges
# but resample from minute or daily in backtest mode
# see catalyst/exchange/ccxt/ccxt_exchange.py:242 for mapping between
# Pandas offet aliases (used by Catalyst) and the CCXT timeframes
if unit.lower() == 'd':
unit = 'D'
alias = '{}D'.format(candle_size)
if data_frequency == 'minute':
data_frequency = 'daily'
elif unit.lower() == 'm' or unit == 'T':
unit = 'T'
alias = '{}T'.format(candle_size)
data_frequency = 'minute'
elif unit.lower() == 'h':
data_frequency = 'minute'
if 'H' in supported_freqs:
unit = 'H'
alias = '{}H'.format(candle_size)
else:
candle_size = candle_size * 60
alias = '{}T'.format(candle_size)
else:
raise InvalidHistoryFrequencyAlias(freq=freq)
return alias, candle_size, unit, data_frequency
def from_ms_timestamp(ms):
return pd.to_datetime(ms, unit='ms', utc=True)
def get_epoch():
return pd.to_datetime('1970-1-1', utc=True)
def get_candles_number_from_minutes(unit, candle_size, minutes):
"""
Get the number of bars needed for the given time interval
in minutes.
Notes
-----
Supports only "T", "D" and "H" units
Parameters
----------
unit: str
candle_size : int
minutes: int
Returns
-------
int
"""
if unit == "T":
res = (float(minutes) / candle_size)
elif unit == "H":
res = (minutes / 60.0) / candle_size
else: # unit == "D"
res = (minutes / 1440.0) / candle_size
return int(math.ceil(res))