Files
catalyst/zipline/data/benchmarks.py
T
Freddie Vargus a12c34c39c MAINT: Skip more rows to match change in treasury data format
I'm not sure what the raw csv pulled from the federal reserve looked like before, but when trying to download fresh treasure data (data not stored in `./zipline`), there is an error that says "Time Period not in list". After checking the raw csv now, it looks like there are 5 header rows rather than just 1, so skipping those rows removes that error.
2017-06-05 11:44:01 -04:00

62 lines
1.9 KiB
Python

#
# Copyright 2013 Quantopian, Inc.
#
# 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.
import numpy as np
import pandas as pd
import pandas_datareader.data as pd_reader
def get_benchmark_returns(symbol, first_date, last_date):
"""
Get a Series of benchmark returns from Google associated with `symbol`.
Default is `SPY`.
Parameters
----------
symbol : str
Benchmark symbol for which we're getting the returns.
first_date : pd.Timestamp
First date for which we want to get data.
last_date : pd.Timestamp
Last date for which we want to get data.
The furthest date that Google goes back to is 1993-02-01. It has missing
data for 2008-12-15, 2009-08-11, and 2012-02-02, so we add data for the
dates for which Google is missing data.
We're also limited to 4000 days worth of data per request. If we make a
request for data that extends past 4000 trading days, we'll still only
receive 4000 days of data.
first_date is **not** included because we need the close from day N - 1 to
compute the returns for day N.
"""
data = pd_reader.DataReader(
symbol,
'google',
first_date,
last_date
)
data = data['Close']
data[pd.Timestamp('2008-12-15')] = np.nan
data[pd.Timestamp('2009-08-11')] = np.nan
data[pd.Timestamp('2012-02-02')] = np.nan
data = data.fillna(method='ffill')
return data.sort_index().tz_localize('UTC').pct_change(1).iloc[1:]