Files
quantconnect--lean/Algorithm.Framework/Selection/EmaCrossUniverseSelectionModel.py
2019-04-03 21:55:43 -03:00

98 lines
4.5 KiB
Python

# QUANTCONNECT.COM - Democratizing Finance, Empowering Individuals.
# Lean Algorithmic Trading Engine v2.0. Copyright 2014 QuantConnect Corporation.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
from clr import AddReference
AddReference("System")
AddReference("QuantConnect.Common")
AddReference("QuantConnect.Indicators")
AddReference("QuantConnect.Algorithm.Framework")
from QuantConnect.Data.UniverseSelection import *
from QuantConnect.Indicators import ExponentialMovingAverage
from Selection.FundamentalUniverseSelectionModel import FundamentalUniverseSelectionModel
class EmaCrossUniverseSelectionModel(FundamentalUniverseSelectionModel):
'''Provides an implementation of FundamentalUniverseSelectionModel that subscribes to
symbols with the larger delta by percentage between the two exponential moving average'''
def __init__(self,
fastPeriod = 100,
slowPeriod = 300,
universeCount = 500,
universeSettings = None,
securityInitializer = None):
'''Initializes a new instance of the EmaCrossUniverseSelectionModel class
Args:
fastPeriod: Fast EMA period
slowPeriod: Slow EMA period
universeCount: Maximum number of members of this universe selection
universeSettings: The settings used when adding symbols to the algorithm, specify null to use algorthm.UniverseSettings
securityInitializer: Optional security initializer invoked when creating new securities, specify null to use algorithm.SecurityInitializer'''
super().__init__(False, universeSettings, securityInitializer)
self.fastPeriod = fastPeriod
self.slowPeriod = slowPeriod
self.universeCount = universeCount
self.tolerance = 0.01
# holds our coarse fundamental indicators by symbol
self.averages = {}
def SelectCoarse(self, algorithm, coarse):
'''Defines the coarse fundamental selection function.
Args:
algorithm: The algorithm instance
coarse: The coarse fundamental data used to perform filtering</param>
Returns:
An enumerable of symbols passing the filter'''
filtered = []
for cf in coarse:
if cf.Symbol not in self.averages:
self.averages[cf.Symbol] = self.SelectionData(cf.Symbol, self.fastPeriod, self.slowPeriod)
# grab th SelectionData instance for this symbol
avg = self.averages.get(cf.Symbol)
# Update returns true when the indicators are ready, so don't accept until they are
# and only pick symbols who have their fastPeriod-day ema over their slowPeriod-day ema
if avg.Update(cf.EndTime, cf.AdjustedPrice) and avg.Fast > avg.Slow * (1 + self.tolerance):
filtered.append(avg)
# prefer symbols with a larger delta by percentage between the two averages
filtered = sorted(filtered, key=lambda avg: avg.ScaledDelta, reverse = True)
# we only need to return the symbol and return 'universeCount' symbols
return [x.Symbol for x in filtered[:self.universeCount]]
# class used to improve readability of the coarse selection function
class SelectionData:
def __init__(self, symbol, fastPeriod, slowPeriod):
self.Symbol = symbol
self.FastEma = ExponentialMovingAverage(fastPeriod)
self.SlowEma = ExponentialMovingAverage(slowPeriod)
@property
def Fast(self):
return float(self.FastEma.Current.Value)
@property
def Slow(self):
return float(self.SlowEma.Current.Value)
# computes an object score of how much large the fast is than the slow
@property
def ScaledDelta(self):
return (self.Fast - self.Slow) / ((self.Fast + self.Slow) / 2)
# updates the EMAFast and EMASlow indicators, returning true when they're both ready
def Update(self, time, value):
return self.SlowEma.Update(time, value) & self.FastEma.Update(time, value)