Add a `bars` keyword arg, as is used with BatchTransform.
Also, instead of overwriting the window_length kwarg with timeperiod,
always use the lookback value from the created TALib function,
as timeperiod will be an input into that value if it exists.
Calculate `window_length` in minute mode so that there are enough
days to cover the minutes in the timeperiod.
For the creation of a TALib transform use timeperiod intsead of
window_length, to be more in the style of TALib usage, since all
TALib functions may not ending up using BatchTransform, so start
the practice of adhering to TALib conventions to make porting and
explanation easier.
The "use_environment" decorator is too side-effectful (e.g.,
connecting to Yahoo! Finance or another data source) to be used as a
decorator to a function that gets evaluated during module load. This
causes problems, e.g., if Zipline is being used in a gevent
environment, when the trading environment created by the decorator
argument tries to use greenlets when gevent hasn't been fully
initialized.
Since the decorator is nothing more than a context-manager wrapper,
this commit removes the decorator and replaces its use with contexts,
i.e., "with" statements.
Instead of searching through the open orders to find the ones
that match the current transactions, now that simulate returns
the pair of transaction and order for which that transaction
was created for, that order can be used where we previously
searched for a modified order.
This should be a runtime improvement since, but not yet verified
via thorough profiling.
The TALib related tests randomly fail, skip for now, as it causes
noise when developing against the latest versions of the codebase.
Should remove skips when TALib is closer to being fully supported.
So that blotter.process_trade doesn't need to reindex the dictionary of
open orders, yield a tuple of (order, transaction) from simulate.
Also, update corresponding unit tests now that the method returns
a generator instead of a list.
- Change the expected type for order information from the string
of the order id to an `Order` object, so that it matches the same
abstraction level as passing in an event.
- Change the order (not to be confused with the parameter named `order`)
of the parameters so that they go from left to right in order of
static -> dynamic, i.e. the parameters most likely to change within
each invoration are the amount and price, with amount more likely
to change than price.
create_transaction accepted both sid and order, which in all cases
was derived from the current event, so remove `sid` and `order`,
replacing them with event
If there is a scenario where sid and order need to be set independently
of each other, then the underlying Transaction object can be called
directly.
Looking towards making writing custom slippage models slightly easier
by removing the redundancy.
In the batch_transform we were incrementing the trading_days counter if there
is a new day event. Thus with a window_length of 1 and daily bars you will
update the batch_transform on the first day which is correct. But with minutes
you update with the first minute bar of the day which is not correct.
This is fixed by calculating the market_close explicity and seeing whether the
event.dt is on or past it.
I also added a unittest to test the correct behavior of this.
Before the change to the RollingPanel, window_length
specified the number of days that should be in a window.
The previous commit broke this if data was minute resolution.
By passing bar='minute' to the batch_transform we internally
multiply the window_length by 60*6.5 to have a full day.
Also adds a (still rudamentary) test for batch_transform
with minute data.
When setting timeperiod in the talib function it subtracts by 1. We then used this subtracted value to set the window_length in the batch_transform which was then not passing a big enough panel. Ultimately this caused the talib transforms to always return nans.
This also makes the unittest more stringent by explicitly comparing the output of the wrapped TALib moving average to pandas rolling_mean().
Finally, this also allows passing of window_length instead of timeperiod to allow usage of the same interface as before.
With the benchmark returns marked at midnight, the performance packet
for a day was emitted *before* any events for that day were processed.
Fix by expecting benchmarks marked at the market close, for backtests
that use minute data but emit performance results daily, so that the
benchmark handles at the end of day.
TST: Also, add test that exercises the event loop with minutely data,
(with benchmarks that are marked end of day), since that combination
was previously uncovered.
The leading date of the date range was never called with update,
because in the main loop the todays_date variable was
incremented before update was called.
Fix by moving the increment to the next trading day to after the
call to update.
So that TALib is still available, but smooth out the ability to
run tests with some issues that bear investigating.
- Ignore MAVP during tests.
- Temporarily use a "regular" member instead of __doc__ string.
(TODO: look into using `type` to generate the class)
- During tests wait until a window exists.
- moved Order and Blotter to zipline.finance.blotter
- moved order method from AlgoSimulator to Blotter
- eliminated the set_order method in algorithm
- moved blotter to the algorithm
Add a test suite of dividend performance that ensures a holiday
is covered, needed because tests usually go over a random test range,
so holiday coverage isn't covered in basic test.
From @fawce.
Refactor PerformanceTracker, Blotter, and AlgorithmSimulator to
work with handling the end of a bar at the AlgorithmSimulator level
instead of within PerformanceTracker.
- PerforamnceTracker and Blotter are longer generators,
both provide functions to process events instead.
- AlgorithmSimulator calls each from within the loop running
over the data generator.
- Change test_perf_tracker utility to be compatible with change
away from PerformanceTracker as a generator.
Has the effect of:
- Fixing the timing of order emission.
- Allow minutely emission of benchmarks, which was prevented
by the extra grouping previously caused by Blotter.
Minutely emission also depends on work for streaming benchmarks
through performance and risk at a minute granularity.
- Create different benchmark containers in performance
depending on emission rate.
- Add a minute close method which updates algorithm and
benchmark returns, and calculates the risk metrics
depending on those methods.
- Provide fake 0.0 values for annualized metrics like
sharpe, sortino, and information, until we figure out
how they should be treated in the context of minutely
calculation.
*NOTE* This does not fully work without the changes to the
simulation loop by @fawce
The bar timestamps for day start and finish, for NYSE traded stocks,
should be 9:31 AM EST to 4:00 PM EST, for a total of 390 minutes.
Fix starting at 9:30 AM and the creation of 391 bars.
Instead of creating a list of benchmarks in the risk module,
stream benchmarks through the system as events, starting from the
algorithm generator.
Works towards more easily setting arbritrary pricing data as
a a benchmark, as well as working towards live minutely benchmarks.
- Add transaction and order types
- Move TransactionSimulator from trading.py to tradesimulation.py
(only used by other members of the tradesimulation module)
- Make Transaction an independent event, like dividend
- Add Blotter class.
- Flatten the transaction events to be independent of trade bar events
- Make orders into events that reach performance (need to add
handling)
- Issue IDs to orders and tracking each transaction's order id.
- Make volume share slippage fill orders independently, rather than
aggregating them into a single transaction.
- Perf tracker holds orders, serializes them with transactions.
- Order state defined and maintained by order class.
- Minutely emission of orders based on last_modified date.
Also, fix double emission of performance results with the last minute.
Change the perf tracker unit tests so that it doesn't rely on an
'extra' event triggering emission.
Unlike daily, minute emission now emits at the end of the bar in
the PerformanceTracker.transform instead of waiting for the next event.
Eddie Hebert