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catalyst/zipline/finance/performance/position_tracker.py
T

433 lines
15 KiB
Python

from __future__ import division
import logbook
import numpy as np
import pandas as pd
from pandas.lib import checknull
try:
# optional cython based OrderedDict
from cyordereddict import OrderedDict
except ImportError:
from collections import OrderedDict
from six import iteritems, itervalues
from zipline.protocol import Event, DATASOURCE_TYPE
from zipline.finance.slippage import Transaction
from zipline.utils.serialization_utils import (
VERSION_LABEL
)
import zipline.protocol as zp
from zipline.assets import (
Equity, Future
)
from zipline.finance.trading import with_environment
from . position import positiondict
log = logbook.Logger('Performance')
class PositionTracker(object):
def __init__(self):
# sid => position object
self.positions = positiondict()
# Arrays for quick calculations of positions value
self._position_amounts = OrderedDict()
self._position_last_sale_prices = OrderedDict()
self._position_value_multipliers = OrderedDict()
self._position_exposure_multipliers = OrderedDict()
self._position_payout_multipliers = OrderedDict()
self._unpaid_dividends = pd.DataFrame(
columns=zp.DIVIDEND_PAYMENT_FIELDS,
)
self._positions_store = zp.Positions()
# Dict, keyed on dates, that contains lists of close position events
# for any Assets in this tracker's positions
self._auto_close_position_sids = {}
@with_environment()
def _retrieve_asset(self, sid, env=None):
return env.asset_finder.retrieve_asset(sid)
def _update_asset(self, sid):
try:
self._position_value_multipliers[sid]
self._position_exposure_multipliers[sid]
self._position_payout_multipliers[sid]
except KeyError:
# Collect the value multipliers from applicable sids
asset = self._retrieve_asset(sid)
if isinstance(asset, Equity):
self._position_value_multipliers[sid] = 1
self._position_exposure_multipliers[sid] = 1
self._position_payout_multipliers[sid] = 0
if isinstance(asset, Future):
self._position_value_multipliers[sid] = 0
self._position_exposure_multipliers[sid] = \
asset.contract_multiplier
self._position_payout_multipliers[sid] = \
asset.contract_multiplier
# Futures are closed on their notice_date
if asset.notice_date:
self._insert_auto_close_position_date(
dt=asset.notice_date,
sid=sid
)
# If the Future does not have a notice_date, it will be closed
# on its expiration_date
elif asset.expiration_date:
self._insert_auto_close_position_date(
dt=asset.expiration_date,
sid=sid
)
def _insert_auto_close_position_date(self, dt, sid):
"""
Inserts the given SID in to the list of positions to be auto-closed by
the given dt.
Parameters
----------
dt : pandas.Timestamp
The date before-which the given SID will be auto-closed
sid : int
The SID of the Asset to be auto-closed
"""
self._auto_close_position_sids.setdefault(dt, set()).add(sid)
def auto_close_position_events(self, next_trading_day):
"""
Generates CLOSE_POSITION events for any SIDs whose auto-close date is
before or equal to the given date.
Parameters
----------
next_trading_day : pandas.Timestamp
The time before-which certain Assets need to be closed
Yields
------
Event
A close position event for any sids that should be closed before
the next_trading_day parameter
"""
past_asset_end_dates = set()
# Check the auto_close_position_dates dict for SIDs to close
for date, sids in self._auto_close_position_sids.items():
if date > next_trading_day:
continue
past_asset_end_dates.add(date)
for sid in sids:
# Yield a CLOSE_POSITION event
event = Event({
'dt': date,
'type': DATASOURCE_TYPE.CLOSE_POSITION,
'sid': sid,
})
yield event
# Clear out past dates
while past_asset_end_dates:
self._auto_close_position_sids.pop(past_asset_end_dates.pop())
def update_last_sale(self, event):
# NOTE, PerformanceTracker already vetted as TRADE type
sid = event.sid
if sid not in self.positions:
return 0
price = event.price
if checknull(price):
return 0
pos = self.positions[sid]
old_price = pos.last_sale_price
pos.last_sale_date = event.dt
pos.last_sale_price = price
self._position_last_sale_prices[sid] = price
# Calculate cash adjustment on assets with multipliers
return ((price - old_price) * self._position_payout_multipliers[sid]
* pos.amount)
def update_positions(self, positions):
# update positions in batch
self.positions.update(positions)
for sid, pos in iteritems(positions):
self._position_amounts[sid] = pos.amount
self._position_last_sale_prices[sid] = pos.last_sale_price
self._update_asset(sid)
def update_position(self, sid, amount=None, last_sale_price=None,
last_sale_date=None, cost_basis=None):
pos = self.positions[sid]
if amount is not None:
pos.amount = amount
self._position_amounts[sid] = amount
self._position_values = None # invalidate cache
self._update_asset(sid=sid)
if last_sale_price is not None:
pos.last_sale_price = last_sale_price
self._position_last_sale_prices[sid] = last_sale_price
self._position_values = None # invalidate cache
if last_sale_date is not None:
pos.last_sale_date = last_sale_date
if cost_basis is not None:
pos.cost_basis = cost_basis
def execute_transaction(self, txn):
# Update Position
# ----------------
sid = txn.sid
position = self.positions[sid]
position.update(txn)
self._position_amounts[sid] = position.amount
self._position_last_sale_prices[sid] = position.last_sale_price
self._update_asset(sid)
def handle_commission(self, commission):
# Adjust the cost basis of the stock if we own it
if commission.sid in self.positions:
self.positions[commission.sid].\
adjust_commission_cost_basis(commission)
@property
def position_values(self):
iter_amount_price_multiplier = zip(
itervalues(self._position_amounts),
itervalues(self._position_last_sale_prices),
itervalues(self._position_value_multipliers),
)
return [
price * amount * multiplier for
price, amount, multiplier in iter_amount_price_multiplier
]
@property
def position_exposures(self):
iter_amount_price_multiplier = zip(
itervalues(self._position_amounts),
itervalues(self._position_last_sale_prices),
itervalues(self._position_exposure_multipliers),
)
return [
price * amount * multiplier for
price, amount, multiplier in iter_amount_price_multiplier
]
def calculate_positions_value(self):
if len(self.position_values) == 0:
return np.float64(0)
return sum(self.position_values)
def calculate_positions_exposure(self):
if len(self.position_exposures) == 0:
return np.float64(0)
return sum(self.position_exposures)
def _longs_count(self):
return sum(1 for i in self.position_exposures if i > 0)
def _long_exposure(self):
return sum(i for i in self.position_exposures if i > 0)
def _long_value(self):
return sum(i for i in self.position_values if i > 0)
def _shorts_count(self):
return sum(1 for i in self.position_exposures if i < 0)
def _short_exposure(self):
return sum(i for i in self.position_exposures if i < 0)
def _short_value(self):
return sum(i for i in self.position_values if i < 0)
def _gross_exposure(self):
return self._long_exposure() + abs(self._short_exposure())
def _gross_value(self):
return self._long_value() + abs(self._short_value())
def _net_exposure(self):
return self.calculate_positions_exposure()
def _net_value(self):
return self.calculate_positions_value()
def handle_split(self, split):
if split.sid in self.positions:
# Make the position object handle the split. It returns the
# leftover cash from a fractional share, if there is any.
position = self.positions[split.sid]
leftover_cash = position.handle_split(split)
self._position_amounts[split.sid] = position.amount
self._position_last_sale_prices[split.sid] = \
position.last_sale_price
self._update_asset(split.sid)
return leftover_cash
def _maybe_earn_dividend(self, dividend):
"""
Take a historical dividend record and return a Series with fields in
zipline.protocol.DIVIDEND_FIELDS (plus an 'id' field) representing
the cash/stock amount we are owed when the dividend is paid.
"""
if dividend['sid'] in self.positions:
return self.positions[dividend['sid']].earn_dividend(dividend)
else:
return zp.dividend_payment()
def earn_dividends(self, dividend_frame):
"""
Given a frame of dividends whose ex_dates are all the next trading day,
calculate and store the cash and/or stock payments to be paid on each
dividend's pay date.
"""
earned = dividend_frame.apply(self._maybe_earn_dividend, axis=1)\
.dropna(how='all')
if len(earned) > 0:
# Store the earned dividends so that they can be paid on the
# dividends' pay_dates.
self._unpaid_dividends = pd.concat(
[self._unpaid_dividends, earned],
)
def _maybe_pay_dividend(self, dividend):
"""
Take a historical dividend record, look up any stored record of
cash/stock we are owed for that dividend, and return a Series
with fields drawn from zipline.protocol.DIVIDEND_PAYMENT_FIELDS.
"""
try:
unpaid_dividend = self._unpaid_dividends.loc[dividend['id']]
return unpaid_dividend
except KeyError:
return zp.dividend_payment()
def pay_dividends(self, dividend_frame):
"""
Given a frame of dividends whose pay_dates are all the next trading
day, grant the cash and/or stock payments that were calculated on the
given dividends' ex dates.
"""
payments = dividend_frame.apply(self._maybe_pay_dividend, axis=1)\
.dropna(how='all')
# Mark these dividends as paid by dropping them from our unpaid
# table.
self._unpaid_dividends.drop(payments.index)
# Add stock for any stock dividends paid. Again, the values here may
# be negative in the case of short positions.
stock_payments = payments[payments['payment_sid'].notnull()]
for _, row in stock_payments.iterrows():
stock = row['payment_sid']
share_count = row['share_count']
# note we create a Position for stock dividend if we don't
# already own the asset
position = self.positions[stock]
position.amount += share_count
self._position_amounts[stock] = position.amount
self._position_last_sale_prices[stock] = position.last_sale_price
self._update_asset(stock)
# Add cash equal to the net cash payed from all dividends. Note that
# "negative cash" is effectively paid if we're short an asset,
# representing the fact that we're required to reimburse the owner of
# the stock for any dividends paid while borrowing.
net_cash_payment = payments['cash_amount'].fillna(0).sum()
return net_cash_payment
def maybe_create_close_position_transaction(self, event):
if not self._position_amounts.get(event.sid):
return None
if 'price' in event:
price = event.price
else:
price = self._position_last_sale_prices[event.sid]
txn = Transaction(
sid=event.sid,
amount=(-1 * self._position_amounts[event.sid]),
dt=event.dt,
price=price,
commission=0,
order_id=0
)
return txn
def get_positions(self):
positions = self._positions_store
for sid, pos in iteritems(self.positions):
if pos.amount == 0:
# Clear out the position if it has become empty since the last
# time get_positions was called. Catching the KeyError is
# faster than checking `if sid in positions`, and this can be
# potentially called in a tight inner loop.
try:
del positions[sid]
except KeyError:
pass
continue
# Note that this will create a position if we don't currently have
# an entry
position = positions[sid]
position.amount = pos.amount
position.cost_basis = pos.cost_basis
position.last_sale_price = pos.last_sale_price
return positions
def get_positions_list(self):
positions = []
for sid, pos in iteritems(self.positions):
if pos.amount != 0:
positions.append(pos.to_dict())
return positions
def __getstate__(self):
state_dict = {}
state_dict['positions'] = dict(self.positions)
state_dict['unpaid_dividends'] = self._unpaid_dividends
STATE_VERSION = 1
state_dict[VERSION_LABEL] = STATE_VERSION
return state_dict
def __setstate__(self, state):
OLDEST_SUPPORTED_STATE = 1
version = state.pop(VERSION_LABEL)
if version < OLDEST_SUPPORTED_STATE:
raise BaseException("PositionTracker saved state is too old.")
self.positions = positiondict()
# note that positions_store is temporary and gets regened from
# .positions
self._positions_store = zp.Positions()
self._unpaid_dividends = state['unpaid_dividends']
# Arrays for quick calculations of positions value
self._position_amounts = OrderedDict()
self._position_last_sale_prices = OrderedDict()
self._position_value_multipliers = OrderedDict()
self._position_exposure_multipliers = OrderedDict()
self._position_payout_multipliers = OrderedDict()
self._auto_close_position_sids = {}
self.update_positions(state['positions'])