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ReStructuredText
818 lines
27 KiB
ReStructuredText
Zipline beginner tutorial
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-------------------------
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Basics
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~~~~~~
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Zipline is an open-source algorithmic trading simulator written in
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Python.
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The source can be found at: https://github.com/quantopian/zipline
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Some benefits include:
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- Realistic: slippage, transaction costs, order delays.
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- Stream-based: Process each event individually, avoids look-ahead
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bias.
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- Batteries included: Common transforms (moving average) as well as
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common risk calculations (Sharpe).
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- Developed and continuously updated by
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`Quantopian <https://www.quantopian.com>`__ which provides an
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easy-to-use web-interface to Zipline, 10 years of minute-resolution
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historical US stock data, and live-trading capabilities. This
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tutorial is directed at users wishing to use Zipline without using
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Quantopian. If you instead want to get started on Quantopian, see
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`here <https://www.quantopian.com/faq#get-started>`__.
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This tutorial assumes that you have zipline correctly installed, see the
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`installation
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instructions <https://github.com/quantopian/zipline#installation>`__ if
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you haven't set up zipline yet.
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Every ``zipline`` algorithm consists of two functions you have to
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define: \* ``initialize(context)`` \* ``handle_data(context, data)``
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Before the start of the algorithm, ``zipline`` calls the
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``initialize()`` function and passes in a ``context`` variable.
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``context`` is a persistent namespace for you to store variables you
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need to access from one algorithm iteration to the next.
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After the algorithm has been initialized, ``zipline`` calls the
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``handle_data()`` function once for each event. At every call, it passes
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the same ``context`` variable and an event-frame called ``data``
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containing the current trading bar with open, high, low, and close
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(OHLC) prices as well as volume for each stock in your universe. For
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more information on these functions, see the `relevant part of the
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Quantopian docs <https://www.quantopian.com/help#api-toplevel>`__.
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My first algorithm
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~~~~~~~~~~~~~~~~~~
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Lets take a look at a very simple algorithm from the ``examples``
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directory, ``buyapple.py``:
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.. code:: python
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!tail ../../zipline/examples/buyapple.py
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.. parsed-literal::
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# Load price data from yahoo.
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data = load_from_yahoo(stocks=['AAPL'], indexes={}, start=start,
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end=end)
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# Create and run the algorithm.
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algo = TradingAlgorithm(initialize=initialize, handle_data=handle_data,
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identifiers=['AAPL'])
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results = algo.run(data)
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analyze(results=results)
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As you can see, we first have to import some functions we would like to
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use. All functions commonly used in your algorithm can be found in
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``zipline.api``. Here we are using ``order()`` which takes two arguments
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-- a security object, and a number specifying how many stocks you would
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like to order (if negative, ``order()`` will sell/short stocks). In this
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case we want to order 10 shares of Apple at each iteration. For more
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documentation on ``order()``, see the `Quantopian
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docs <https://www.quantopian.com/help#api-order>`__.
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You don't have to use the ``symbol()`` function and could just pass in
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``AAPL`` directly but it is good practice as this way your code will be
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Quantopian compatible.
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Finally, the ``record()`` function allows you to save the value of a
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variable at each iteration. You provide it with a name for the variable
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together with the variable itself: ``varname=var``. After the algorithm
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finished running you will have access to each variable value you tracked
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with ``record()`` under the name you provided (we will see this further
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below). You also see how we can access the current price data of the
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AAPL stock in the ``data`` event frame (for more information see
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`here <https://www.quantopian.com/help#api-event-properties>`__.
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Running the algorithm
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~~~~~~~~~~~~~~~~~~~~~
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To now test this algorithm on financial data, ``zipline`` provides two
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interfaces. A command-line interface and an ``IPython Notebook``
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interface.
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Command line interface
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^^^^^^^^^^^^^^^^^^^^^^
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After you installed zipline you should be able to execute the following
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from your command line (e.g. ``cmd.exe`` on Windows, or the Terminal app
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on OSX):
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.. code:: python
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!run_algo.py --help
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.. parsed-literal::
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usage: run_algo.py [-h] [-c FILE] [--algofile ALGOFILE] [--data-frequency {minute,daily}] [--start START] [--end END]
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[--capital_base CAPITAL_BASE] [--source {yahoo}] [--source_time_column SOURCE_TIME_COLUMN] [--symbols SYMBOLS]
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[--output OUTPUT] [--metadata_path METADATA_PATH] [--metadata_index METADATA_INDEX] [--print-algo] [--no-print-algo]
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Zipline version 0.8.3.
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optional arguments:
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-h, --help show this help message and exit
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-c FILE, --conf_file FILE
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Specify config file
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--algofile ALGOFILE, -f ALGOFILE
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--data-frequency {minute,daily}
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--start START, -s START
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--end END, -e END
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--capital_base CAPITAL_BASE
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--source {yahoo}, -d {yahoo}
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--source_time_column SOURCE_TIME_COLUMN, -t SOURCE_TIME_COLUMN
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--symbols SYMBOLS
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--output OUTPUT, -o OUTPUT
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--metadata_path METADATA_PATH, -m METADATA_PATH
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--metadata_index METADATA_INDEX, -x METADATA_INDEX
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--print-algo, -p
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--no-print-algo, -q
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Note that you have to omit the preceding '!' when you call
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``run_algo.py``, this is only required by the IPython Notebook in which
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this tutorial was written.
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As you can see there are a couple of flags that specify where to find
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your algorithm (``-f``) as well as parameters specifying which stock
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data to load from Yahoo! finance (``--symbols``) and the time-range
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(``--start`` and ``--end``). Finally, you'll want to save the
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performance metrics of your algorithm so that you can analyze how it
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performed. This is done via the ``--output`` flag and will cause it to
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write the performance ``DataFrame`` in the pickle Python file format.
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Note that you can also define a configuration file with these parameters
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that you can then conveniently pass to the ``-c`` option so that you
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don't have to supply the command line args all the time (see the .conf
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files in the examples directory).
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Thus, to execute our algorithm from above and save the results to
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``buyapple_out.pickle`` we would call ``run_algo.py`` as follows:
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.. code:: python
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!run_algo.py -f ../../zipline/examples/buyapple.py --start 2000-1-1 --end 2014-1-1 --symbols AAPL -o buyapple_out.pickle
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.. parsed-literal::
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AAPL
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[2015-11-04 22:45:32.820166] INFO: Performance: Simulated 3521 trading days out of 3521.
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[2015-11-04 22:45:32.820314] INFO: Performance: first open: 2000-01-03 14:31:00+00:00
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[2015-11-04 22:45:32.820401] INFO: Performance: last close: 2013-12-31 21:00:00+00:00
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``run_algo.py`` first outputs the algorithm contents. It then fetches
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historical price and volume data of Apple from Yahoo! finance in the
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desired time range, calls the ``initialize()`` function, and then
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streams the historical stock price day-by-day through ``handle_data()``.
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After each call to ``handle_data()`` we instruct ``zipline`` to order 10
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stocks of AAPL. After the call of the ``order()`` function, ``zipline``
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enters the ordered stock and amount in the order book. After the
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``handle_data()`` function has finished, ``zipline`` looks for any open
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orders and tries to fill them. If the trading volume is high enough for
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this stock, the order is executed after adding the commission and
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applying the slippage model which models the influence of your order on
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the stock price, so your algorithm will be charged more than just the
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stock price \* 10. (Note, that you can also change the commission and
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slippage model that ``zipline`` uses, see the `Quantopian
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docs <https://www.quantopian.com/help#ide-slippage>`__ for more
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information).
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Note that there is also an ``analyze()`` function printed.
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``run_algo.py`` will try and look for a file with the ending with
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``_analyze.py`` and the same name of the algorithm (so
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``buyapple_analyze.py``) or an ``analyze()`` function directly in the
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script. If an ``analyze()`` function is found it will be called *after*
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the simulation has finished and passed in the performance ``DataFrame``.
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(The reason for allowing specification of an ``analyze()`` function in a
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separate file is that this way ``buyapple.py`` remains a valid
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Quantopian algorithm that you can copy&paste to the platform).
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Lets take a quick look at the performance ``DataFrame``. For this, we
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use ``pandas`` from inside the IPython Notebook and print the first ten
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rows. Note that ``zipline`` makes heavy usage of ``pandas``, especially
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for data input and outputting so it's worth spending some time to learn
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it.
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.. code:: python
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import pandas as pd
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perf = pd.read_pickle('buyapple_out.pickle') # read in perf DataFrame
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perf.head()
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.. raw:: html
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<div style="max-height:1000px;max-width:1500px;overflow:auto;">
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<table border="1" class="dataframe">
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<thead>
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<tr style="text-align: right;">
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<th></th>
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<th>AAPL</th>
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<th>algo_volatility</th>
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<th>algorithm_period_return</th>
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<th>alpha</th>
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<th>benchmark_period_return</th>
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<th>benchmark_volatility</th>
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<th>beta</th>
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<th>capital_used</th>
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<th>ending_cash</th>
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<th>ending_exposure</th>
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<th>...</th>
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<th>short_exposure</th>
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<th>short_value</th>
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<th>shorts_count</th>
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<th>sortino</th>
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<th>starting_cash</th>
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<th>starting_exposure</th>
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<th>starting_value</th>
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<th>trading_days</th>
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<th>transactions</th>
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<th>treasury_period_return</th>
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</tr>
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</thead>
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<tbody>
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<tr>
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<th>2000-01-03 21:00:00</th>
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<td>3.738314</td>
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<td>0.000000e+00</td>
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<td>0.000000e+00</td>
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<td>-0.065800</td>
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<td>-0.009549</td>
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<td>0.000000</td>
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<td>0.000000</td>
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<td>0.00000</td>
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<td>10000000.00000</td>
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<td>0.00000</td>
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<td>...</td>
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<td>0</td>
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<td>0</td>
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<td>0</td>
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<td>0.000000</td>
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<td>10000000.00000</td>
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<td>0.00000</td>
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<td>0.00000</td>
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<td>1</td>
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<td>[]</td>
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<td>0.0658</td>
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</tr>
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<tr>
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<th>2000-01-04 21:00:00</th>
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<td>3.423135</td>
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<td>3.367492e-07</td>
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<td>-3.000000e-08</td>
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<td>-0.064897</td>
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<td>-0.047528</td>
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<td>0.323229</td>
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<td>0.000001</td>
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<td>-34.53135</td>
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<td>9999965.46865</td>
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<td>34.23135</td>
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<td>...</td>
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<td>0</td>
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<td>0</td>
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<td>0</td>
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<td>0.000000</td>
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<td>10000000.00000</td>
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<td>0.00000</td>
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<td>0.00000</td>
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<td>2</td>
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<td>[{u'order_id': u'513357725cb64a539e3dd02b47da7...</td>
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<td>0.0649</td>
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</tr>
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<tr>
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<th>2000-01-05 21:00:00</th>
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<td>3.473229</td>
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<td>4.001918e-07</td>
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<td>-9.906000e-09</td>
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<td>-0.066196</td>
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<td>-0.045697</td>
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<td>0.329321</td>
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<td>0.000001</td>
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<td>-35.03229</td>
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<td>9999930.43636</td>
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<td>69.46458</td>
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<td>...</td>
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<td>0</td>
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<td>0</td>
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<td>0</td>
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<td>0.000000</td>
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<td>9999965.46865</td>
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<td>34.23135</td>
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<td>34.23135</td>
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<td>3</td>
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<td>[{u'order_id': u'd7d4ad03cfec4d578c0d817dc3829...</td>
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<td>0.0662</td>
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</tr>
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<tr>
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<th>2000-01-06 21:00:00</th>
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<td>3.172661</td>
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<td>4.993979e-06</td>
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<td>-6.410420e-07</td>
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<td>-0.065758</td>
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<td>-0.044785</td>
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<td>0.298325</td>
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<td>-0.000006</td>
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<td>-32.02661</td>
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<td>9999898.40975</td>
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<td>95.17983</td>
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<td>...</td>
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<td>0</td>
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<td>0</td>
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<td>0</td>
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<td>-12731.780516</td>
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<td>9999930.43636</td>
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<td>69.46458</td>
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<td>69.46458</td>
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<td>4</td>
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<td>[{u'order_id': u'1fbf5e9bfd7c4d9cb2e8383e1085e...</td>
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<td>0.0657</td>
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</tr>
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<tr>
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<th>2000-01-07 21:00:00</th>
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<td>3.322945</td>
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<td>5.977002e-06</td>
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<td>-2.201900e-07</td>
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<td>-0.065206</td>
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<td>-0.018908</td>
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<td>0.375301</td>
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<td>0.000005</td>
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<td>-33.52945</td>
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<td>9999864.88030</td>
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<td>132.91780</td>
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<td>...</td>
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<td>0</td>
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<td>0</td>
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<td>0</td>
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<td>-12629.274583</td>
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<td>9999898.40975</td>
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<td>95.17983</td>
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<td>95.17983</td>
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<td>5</td>
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<td>[{u'order_id': u'9ea6b142ff09466b9113331a37437...</td>
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<td>0.0652</td>
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</tr>
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</tbody>
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</table>
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<p>5 rows × 39 columns</p>
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</div>
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As you can see, there is a row for each trading day, starting on the
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first business day of 2000. In the columns you can find various
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information about the state of your algorithm. The very first column
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``AAPL`` was placed there by the ``record()`` function mentioned earlier
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and allows us to plot the price of apple. For example, we could easily
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examine now how our portfolio value changed over time compared to the
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AAPL stock price.
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.. code:: python
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%pylab inline
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figsize(12, 12)
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import matplotlib.pyplot as plt
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ax1 = plt.subplot(211)
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perf.portfolio_value.plot(ax=ax1)
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ax1.set_ylabel('portfolio value')
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ax2 = plt.subplot(212, sharex=ax1)
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perf.AAPL.plot(ax=ax2)
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ax2.set_ylabel('AAPL stock price')
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.. parsed-literal::
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Populating the interactive namespace from numpy and matplotlib
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.. parsed-literal::
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<matplotlib.text.Text at 0x7ff5c6147f90>
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.. image:: tutorial_files/tutorial_11_2.png
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As you can see, our algorithm performance as assessed by the
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``portfolio_value`` closely matches that of the AAPL stock price. This
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is not surprising as our algorithm only bought AAPL every chance it got.
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IPython Notebook
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~~~~~~~~~~~~~~~~
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The `IPython Notebook <http://ipython.org/notebook.html>`__ is a very
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powerful browser-based interface to a Python interpreter (this tutorial
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was written in it). As it is already the de-facto interface for most
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quantitative researchers ``zipline`` provides an easy way to run your
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algorithm inside the Notebook without requiring you to use the CLI.
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To use it you have to write your algorithm in a cell and let ``zipline``
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know that it is supposed to run this algorithm. This is done via the
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``%%zipline`` IPython magic command that is available after you
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``import zipline`` from within the IPython Notebook. This magic takes
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the same arguments as the command line interface described above. Thus
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to run the algorithm from above with the same parameters we just have to
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execute the following cell after importing ``zipline`` to register the
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magic.
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.. code:: python
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import zipline
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.. code:: python
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%%zipline --start 2000-1-1 --end 2014-1-1 --symbols AAPL -o perf_ipython
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from zipline.api import symbol, order, record
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def initialize(context):
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pass
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def handle_data(context, data):
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order(symbol('AAPL'), 10)
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record(AAPL=data[symbol('AAPL')].price)
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.. parsed-literal::
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AAPL
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Note that we did not have to specify an input file as above since the
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magic will use the contents of the cell and look for your algorithm
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functions there. Also, instead of defining an output file we are
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specifying a variable name with ``-o`` that will be created in the name
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space and contain the performance ``DataFrame`` we looked at above.
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.. code:: python
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perf_ipython.head()
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.. raw:: html
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<div style="max-height:1000px;max-width:1500px;overflow:auto;">
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<table border="1" class="dataframe">
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<thead>
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<tr style="text-align: right;">
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<th></th>
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<th>AAPL</th>
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<th>algo_volatility</th>
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<th>algorithm_period_return</th>
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<th>alpha</th>
|
||
<th>benchmark_period_return</th>
|
||
<th>benchmark_volatility</th>
|
||
<th>beta</th>
|
||
<th>capital_used</th>
|
||
<th>ending_cash</th>
|
||
<th>ending_exposure</th>
|
||
<th>...</th>
|
||
<th>short_exposure</th>
|
||
<th>short_value</th>
|
||
<th>shorts_count</th>
|
||
<th>sortino</th>
|
||
<th>starting_cash</th>
|
||
<th>starting_exposure</th>
|
||
<th>starting_value</th>
|
||
<th>trading_days</th>
|
||
<th>transactions</th>
|
||
<th>treasury_period_return</th>
|
||
</tr>
|
||
</thead>
|
||
<tbody>
|
||
<tr>
|
||
<th>2000-01-03 21:00:00</th>
|
||
<td>3.738314</td>
|
||
<td>0.000000e+00</td>
|
||
<td>0.000000e+00</td>
|
||
<td>-0.065800</td>
|
||
<td>-0.009549</td>
|
||
<td>0.000000</td>
|
||
<td>0.000000</td>
|
||
<td>0.00000</td>
|
||
<td>10000000.00000</td>
|
||
<td>0.00000</td>
|
||
<td>...</td>
|
||
<td>0</td>
|
||
<td>0</td>
|
||
<td>0</td>
|
||
<td>0.000000</td>
|
||
<td>10000000.00000</td>
|
||
<td>0.00000</td>
|
||
<td>0.00000</td>
|
||
<td>1</td>
|
||
<td>[]</td>
|
||
<td>0.0658</td>
|
||
</tr>
|
||
<tr>
|
||
<th>2000-01-04 21:00:00</th>
|
||
<td>3.423135</td>
|
||
<td>3.367492e-07</td>
|
||
<td>-3.000000e-08</td>
|
||
<td>-0.064897</td>
|
||
<td>-0.047528</td>
|
||
<td>0.323229</td>
|
||
<td>0.000001</td>
|
||
<td>-34.53135</td>
|
||
<td>9999965.46865</td>
|
||
<td>34.23135</td>
|
||
<td>...</td>
|
||
<td>0</td>
|
||
<td>0</td>
|
||
<td>0</td>
|
||
<td>0.000000</td>
|
||
<td>10000000.00000</td>
|
||
<td>0.00000</td>
|
||
<td>0.00000</td>
|
||
<td>2</td>
|
||
<td>[{u'commission': 0.3, u'amount': 10, u'sid': 0...</td>
|
||
<td>0.0649</td>
|
||
</tr>
|
||
<tr>
|
||
<th>2000-01-05 21:00:00</th>
|
||
<td>3.473229</td>
|
||
<td>4.001918e-07</td>
|
||
<td>-9.906000e-09</td>
|
||
<td>-0.066196</td>
|
||
<td>-0.045697</td>
|
||
<td>0.329321</td>
|
||
<td>0.000001</td>
|
||
<td>-35.03229</td>
|
||
<td>9999930.43636</td>
|
||
<td>69.46458</td>
|
||
<td>...</td>
|
||
<td>0</td>
|
||
<td>0</td>
|
||
<td>0</td>
|
||
<td>0.000000</td>
|
||
<td>9999965.46865</td>
|
||
<td>34.23135</td>
|
||
<td>34.23135</td>
|
||
<td>3</td>
|
||
<td>[{u'commission': 0.3, u'amount': 10, u'sid': 0...</td>
|
||
<td>0.0662</td>
|
||
</tr>
|
||
<tr>
|
||
<th>2000-01-06 21:00:00</th>
|
||
<td>3.172661</td>
|
||
<td>4.993979e-06</td>
|
||
<td>-6.410420e-07</td>
|
||
<td>-0.065758</td>
|
||
<td>-0.044785</td>
|
||
<td>0.298325</td>
|
||
<td>-0.000006</td>
|
||
<td>-32.02661</td>
|
||
<td>9999898.40975</td>
|
||
<td>95.17983</td>
|
||
<td>...</td>
|
||
<td>0</td>
|
||
<td>0</td>
|
||
<td>0</td>
|
||
<td>-12731.780516</td>
|
||
<td>9999930.43636</td>
|
||
<td>69.46458</td>
|
||
<td>69.46458</td>
|
||
<td>4</td>
|
||
<td>[{u'commission': 0.3, u'amount': 10, u'sid': 0...</td>
|
||
<td>0.0657</td>
|
||
</tr>
|
||
<tr>
|
||
<th>2000-01-07 21:00:00</th>
|
||
<td>3.322945</td>
|
||
<td>5.977002e-06</td>
|
||
<td>-2.201900e-07</td>
|
||
<td>-0.065206</td>
|
||
<td>-0.018908</td>
|
||
<td>0.375301</td>
|
||
<td>0.000005</td>
|
||
<td>-33.52945</td>
|
||
<td>9999864.88030</td>
|
||
<td>132.91780</td>
|
||
<td>...</td>
|
||
<td>0</td>
|
||
<td>0</td>
|
||
<td>0</td>
|
||
<td>-12629.274583</td>
|
||
<td>9999898.40975</td>
|
||
<td>95.17983</td>
|
||
<td>95.17983</td>
|
||
<td>5</td>
|
||
<td>[{u'commission': 0.3, u'amount': 10, u'sid': 0...</td>
|
||
<td>0.0652</td>
|
||
</tr>
|
||
</tbody>
|
||
</table>
|
||
<p>5 rows × 39 columns</p>
|
||
</div>
|
||
|
||
|
||
|
||
Manual (advanced)
|
||
~~~~~~~~~~~~~~~~~
|
||
|
||
If you are happy with either way above you can safely skip this passage.
|
||
To provide a closer look at how ``zipline`` actually works it is
|
||
instructive to see how we run an algorithm without any of the interfaces
|
||
demonstrated above which hide the actual ``zipline`` API.
|
||
|
||
.. code:: python
|
||
|
||
import pytz
|
||
from datetime import datetime
|
||
|
||
from zipline.algorithm import TradingAlgorithm
|
||
from zipline.utils.factory import load_bars_from_yahoo
|
||
|
||
# Load data manually from Yahoo! finance
|
||
start = datetime(2000, 1, 1, 0, 0, 0, 0, pytz.utc)
|
||
end = datetime(2012, 1, 1, 0, 0, 0, 0, pytz.utc)
|
||
data = load_bars_from_yahoo(stocks=['AAPL'], start=start,
|
||
end=end)
|
||
|
||
# Define algorithm
|
||
def initialize(context):
|
||
pass
|
||
|
||
def handle_data(context, data):
|
||
order(symbol('AAPL'), 10)
|
||
record(AAPL=data[symbol('AAPL')].price)
|
||
|
||
# Create algorithm object passing in initialize and
|
||
# handle_data functions
|
||
algo_obj = TradingAlgorithm(initialize=initialize,
|
||
handle_data=handle_data)
|
||
|
||
# Run algorithm
|
||
perf_manual = algo_obj.run(data)
|
||
|
||
|
||
.. parsed-literal::
|
||
|
||
AAPL
|
||
|
||
|
||
As you can see, we again define the functions as above but we manually
|
||
pass them to the ``TradingAlgorithm`` class which is the main
|
||
``zipline`` class for running algorithms. We also manually load the data
|
||
using ``load_bars_from_yahoo()`` and pass it to the
|
||
``TradingAlgorithm.run()`` method which kicks off the backtest
|
||
simulation.
|
||
|
||
Access to previous prices using ``history``
|
||
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
||
|
||
Working example: Dual Moving Average Cross-Over
|
||
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
||
|
||
The Dual Moving Average (DMA) is a classic momentum strategy. It's
|
||
probably not used by any serious trader anymore but is still very
|
||
instructive. The basic idea is that we compute two rolling or moving
|
||
averages (mavg) -- one with a longer window that is supposed to capture
|
||
long-term trends and one shorter window that is supposed to capture
|
||
short-term trends. Once the short-mavg crosses the long-mavg from below
|
||
we assume that the stock price has upwards momentum and long the stock.
|
||
If the short-mavg crosses from above we exit the positions as we assume
|
||
the stock to go down further.
|
||
|
||
As we need to have access to previous prices to implement this strategy
|
||
we need a new concept: History
|
||
|
||
``history()`` is a convenience function that keeps a rolling window of
|
||
data for you. The first argument is the number of bars you want to
|
||
collect, the second argument is the unit (either ``'1d'`` for ``'1m'``
|
||
but note that you need to have minute-level data for using ``1m``). For
|
||
a more detailed description ``history()``'s features, see the
|
||
`Quantopian docs <https://www.quantopian.com/help#ide-history>`__. While
|
||
you can directly use the ``history()`` function on Quantopian, in
|
||
``zipline`` you have to register each history container you want to use
|
||
with ``add_history()`` and pass it the same arguments as the history
|
||
function below. Lets look at the strategy which should make this clear:
|
||
|
||
.. code:: python
|
||
|
||
%%zipline --start 2000-1-1 --end 2014-1-1 --symbols AAPL -o perf_dma
|
||
|
||
|
||
from zipline.api import order_target, record, symbol, history, add_history
|
||
import numpy as np
|
||
|
||
def initialize(context):
|
||
# Register 2 histories that track daily prices,
|
||
# one with a 100 window and one with a 300 day window
|
||
add_history(100, '1d', 'price')
|
||
add_history(300, '1d', 'price')
|
||
|
||
context.i = 0
|
||
|
||
|
||
def handle_data(context, data):
|
||
# Skip first 300 days to get full windows
|
||
context.i += 1
|
||
if context.i < 300:
|
||
return
|
||
|
||
# Compute averages
|
||
# history() has to be called with the same params
|
||
# from above and returns a pandas dataframe.
|
||
short_mavg = history(100, '1d', 'price').mean()
|
||
long_mavg = history(300, '1d', 'price').mean()
|
||
|
||
# Trading logic
|
||
if short_mavg[0] > long_mavg[0]:
|
||
# order_target orders as many shares as needed to
|
||
# achieve the desired number of shares.
|
||
order_target(symbol('AAPL'), 100)
|
||
elif short_mavg[0] < long_mavg[0]:
|
||
order_target(symbol('AAPL'), 0)
|
||
|
||
# Save values for later inspection
|
||
record(AAPL=data[symbol('AAPL')].price,
|
||
short_mavg=short_mavg[0],
|
||
long_mavg=long_mavg[0])
|
||
|
||
|
||
def analyze(context, perf):
|
||
fig = plt.figure()
|
||
ax1 = fig.add_subplot(211)
|
||
perf.portfolio_value.plot(ax=ax1)
|
||
ax1.set_ylabel('portfolio value in $')
|
||
|
||
ax2 = fig.add_subplot(212)
|
||
perf['AAPL'].plot(ax=ax2)
|
||
perf[['short_mavg', 'long_mavg']].plot(ax=ax2)
|
||
|
||
perf_trans = perf.ix[[t != [] for t in perf.transactions]]
|
||
buys = perf_trans.ix[[t[0]['amount'] > 0 for t in perf_trans.transactions]]
|
||
sells = perf_trans.ix[
|
||
[t[0]['amount'] < 0 for t in perf_trans.transactions]]
|
||
ax2.plot(buys.index, perf.short_mavg.ix[buys.index],
|
||
'^', markersize=10, color='m')
|
||
ax2.plot(sells.index, perf.short_mavg.ix[sells.index],
|
||
'v', markersize=10, color='k')
|
||
ax2.set_ylabel('price in $')
|
||
plt.legend(loc=0)
|
||
plt.show()
|
||
|
||
|
||
.. parsed-literal::
|
||
|
||
AAPL
|
||
|
||
|
||
|
||
.. image:: tutorial_files/tutorial_22_1.png
|
||
|
||
|
||
Here we are explicitly defining an ``analyze()`` function that gets
|
||
automatically called once the backtest is done (this is not possible on
|
||
Quantopian currently).
|
||
|
||
Although it might not be directly apparent, the power of ``history()``
|
||
(pun intended) can not be under-estimated as most algorithms make use of
|
||
prior market developments in one form or another. You could easily
|
||
devise a strategy that trains a classifier with
|
||
`scikit-learn <http://scikit-learn.org/stable/>`__ which tries to
|
||
predict future market movements based on past prices (note, that most of
|
||
the ``scikit-learn`` functions require ``numpy.ndarray``\ s rather than
|
||
``pandas.DataFrame``\ s, so you can simply pass the underlying
|
||
``ndarray`` of a ``DataFrame`` via ``.values``).
|
||
|
||
We also used the ``order_target()`` function above. This and other
|
||
functions like it can make order management and portfolio rebalancing
|
||
much easier. See the `Quantopian documentation on order
|
||
functions <https://www.quantopian.com/help#api-order-methods>`__ fore
|
||
more details.
|
||
|
||
Conclusions
|
||
~~~~~~~~~~~
|
||
|
||
We hope that this tutorial gave you a little insight into the
|
||
architecture, API, and features of ``zipline``. For next steps, check
|
||
out some of the
|
||
`examples <https://github.com/quantopian/zipline/tree/master/zipline/examples>`__.
|
||
|
||
Feel free to ask questions on `our mailing
|
||
list <https://groups.google.com/forum/#!forum/zipline>`__, report
|
||
problems on our `GitHub issue
|
||
tracker <https://github.com/quantopian/zipline/issues?state=open>`__,
|
||
`get
|
||
involved <https://github.com/quantopian/zipline/wiki/Contribution-Requests>`__,
|
||
and `checkout Quantopian <https://quantopian.com>`__.
|