_convert_asset_str_fields was added to address the fact that the
unicode returned by SQLAlchemy was causing test failures, in
particular test_repr and test_root_symbols failed because of the
leading 'u' character in the unicode of python-2.x. Later it was
pointed out that this method would behave differently in python 2
and 3, in particular the str() method would return bytes in python
2 and unicode in python 3. After investigating it was found that
the _convert_asset_str_fields was no longer necessary. It is unclear
why the original tests were failing. It is not due to SQLAlchemy
versions, as tests pass for version >1 and <1.
lookup_symbol_resolve_multiple was identical to lookup_symbol, except that lookup_symbol performed upper-casing of the input string and lookup_symbol would return Nones. Now, lookup_symbol has a kwarg 'default_None=True' and all symbols are upper-cased on insertion and request.
- Fixes an error where Modeling API data known as of the close of `day
N` would be shown to algorithms during `before_trading_start` as of
the close of the same day. Algorithms should now only receive data
during `before_trading_start/handle_data` that was known as of the
simulation time at which the function would be called.
- All Term instances now have a `mask` attribute that must be a `Filter`
or an instance of `AssetExists()`. `mask` can be used to specify that
a Factor should be computed in a manner that ignores the values that
were not `True` in the mask.
- Changed the interface for `FFCLoader.load_adjusted_array` and
`Term._compute` from `(columns, mask)`, with mask as a DataFrame, to
`(columns, dates, assets, mask)`, where mask is a numpy array. This
is primarily to avoid having to reconstruct extra DataFrames when
using masks produced by non `AssetExists` filters.
- Adds `BoundColumn.latest`, which gives the most-recently-known value
of a column.
This commit removes the ability to reference a shared TradingEnvironment through the zipline.finance.trading module. In place, the classes that require a TradingEnvironment, or its child AssetFinder, contain their own references to those objects.
This commit also adds serialization utilities that allow for the pickling/unpickling of objects without unintentionally their TradingEnvironments or AssetFinders.
Bug fixes include:
- Do not call float on tuples
- Correct indentation
- Do not call value() on int
- Use fuzzy correctly
- Use symbol for lookup
- Ensure we raise Error
Stewart Douglas