Release Notes¶
Release 0.11.0¶
| Release: | 0.11.0 |
|---|
New Expressions¶
Many new string utility expressions were added that follow the Pandas vectorized string methods API closely http://pandas.pydata.org/pandas-docs/stable/text.html#text-string-methods. These are gathered under the
.strsub-namespace, allowing the user to say:t.col.str.lower()
to compute a new column with the string contents lowercased.
Likewise, many new datetime utility expressions were added to the
.dtsub-namespace, following Pandas vectorized datetime methods API http://pandas.pydata.org/pandas-docs/stable/timeseries.html.
Improved Expressions¶
None
New Backends¶
None
Improved Backends¶
None
Experimental Features¶
None
API Changes¶
The following functions were deprecated in favor of equivalent functions without the str_ name prefix:
deprecated function replacement function str_len()len()str_upper()upper()str_lower()lower()str_cat()cat()
Bug Fixes¶
None
Miscellaneous¶
None
Release 0.10.2¶
| Release: | 0.10.2 |
|---|
New Expressions¶
None
New Backends¶
None
Improved Backends¶
- To allow access to the
mapandapplyexpressions in client / server interactions when in a trusted environment, new_trustedversions of the several defaultSerializationFormatinstances were added. These trusted variants allow (de)serialization of builtin functions, NumPy functions, and Pandas functions. They are intentially kept separate from the default versions to ensure they are not accidentally enabled in untrusted environments (#1497 #1504).
Experimental Features¶
None
API Changes¶
None
Bug Fixes¶
- Fixed a bug with
to_tree()andsliceobjects. Have to change the order of cases into_tree()to ensuresliceobjects are handled before lookups inside thenamesnamespace (#1516). - Perform more input validation for
sort()expression arguments (#1517). - Fixes issue with string and datetime coercions on Pandas objects (#1519 #1524).
- Fixed a bug with
isinandSelections on sql selectables (#1528).
Miscellaneous¶
Expression Identity Rework¶
Expression are now memoized by their inputs. This means that two identical
expressions will always be the same object, or that a.isidentical(b) is the
same as a is b. isidentical is called hundreds of thousands of times in
a normal blaze workload. Moving more work to expression construction time has
been shown to dramatically improve compute times when the expressions grow in
complexity or size. In the past, blaze was spending linear time relative to the
expression size to compare expressions because it needed to recurse through the
entire expression tree but now it can do isidentical in constant time.
Users should still use a.isidentical(b) instead of a is b because we
reserve the right to add more arguments or change the implementation of
isidentical in the future.
Release 0.10.1¶
| Release: | 0.10.1 |
|---|---|
| Date: | TBD |
New Expressions¶
None
Improved Expressions¶
None
New Backends¶
None
Improved Backends¶
Experimental Features¶
- The
str_cat()expression was added, mirroring Pandas’Series.str.cat()API (#1496).
API Changes¶
None
Bug Fixes¶
Miscellaneous¶
None
Release 0.10.0¶
| Release: | 0.10.0 |
|---|---|
| Date: | TBD |
New Expressions¶
The
sampleexpression allows random sampling of rows to facilitate interactive data exploration (#1410). It is implemented for the Pandas, Dask, SQL, and Python backends.Adds
coalesce()expression which takes two arguments and returns the first non missing value. If both are missing then the result is missing. For example:coalesce(1, 2) == 1,coalesce(None, 1)== 1, andcoalesce(None, None) == None. This is inspired by the sql function of the same name (#1409).Adds
cast()expression to reinterpret an expression’s dshape. This is based on C++reinterpret_cast, or just normal C casts. For example:symbol('s', 'int32').cast('uint32').dshape == dshape('uint32'). This expression has no affect on the computation, it merely tells blaze to treat the result of the expression as the new dshape. The compute definition forcastis simply:@dispatch(Cast, object) def compute_up(expr, data, **kwargs): return data
(#1409).
Improved Expressions¶
- The test suite was expanded to validate proper expression input error handling (#1420).
- The
truncate()function was refactored to raise an exception for incorrect inputs, rather than using assertions (#1443). - The docstring for
Mergewas expanded to include examples usingLabelto control the ordering of the columns in the result (#1447).
New Backends¶
None
Improved Backends¶
Experimental Features¶
- The
str_upperandstr_lowerexpressions were added for the Pandas and SQL backends (#1462). These are marked experimental since their names are subject to change. More string methods will be added in coming versions.
API Changes¶
- The
strlenexpression was deprecated in favor ofstr_len(#1462). - Long deprecated
Table()andTableSymbol()were removed (#1441). TheTableSymboltests intest_table.pywere migrated totest_symbol.py. Data()has been deprecated in favor ofdata().InteractiveSymbolhas been deprecated and temporarily replaced by_Data. These deprecations will be in place for the 0.10 release. In the 0.11 release,_Datawill be renamed toData, calls todata()will createDatainstances, andInteractiveSymbolwill be removed (#1431 and #1421).compute()has a new keyword argumentreturn_typewhich defaults to'native'(#1401, #1411, #1417), which preserves existing behavior. In the 0.11 release,return_typewill be changed to default to'core', which willodonon-core backends into core backends as the final step in a call tocompute.- Due to API instability and on the recommendation of DyND developers, we removed the DyND dependency temporarily (#1379). When DyND achieves its 1.0 release, DyND will be re-incorporated into Blaze. The existing DyND support in Blaze was rudimentary and based on an egregiously outdated and buggy version of DyND. We are aware of no actual use of DyND via Blaze in practice.
- The
Expr__repr__method’s triggering of implicit computation has been deprecated. Using this aspect of Blaze will trigger aDeprecationWarningin version 0.10, and this behavior will be replaced by a standard (boring)__repr__implementation in version 0.11. Users can explicitly trigger a computation to see a quick view of the results of an interactive expression by means of thepeek()method. By setting theuse_new_reprflag toTrue, users can use the new (boring)__repr__implementation in version 0.10 (#1414 and #1395).
Bug Fixes¶
- The
str_upperandstr_lowerschemas were fixed to pass through their underlying_child‘s schema to ensure option types are handled correctly (#1472). - Fixed a bug with Pandas’ implementation of
compute_uponBroadcastexpressions (#1442). Added tests for Pandas frame and series and dask dataframes onBroadcastexpressions. - Fixed a bug with
Sampleon SQL backends (#1452 #1423 #1424 #1425). - Fixed several bugs relating to adding new datasets to blaze server instances (#1459). Blaze server will make a best effort to ensure that the added dataset is valid and loadable; if not, it will return appropriate HTTP status codes.
Miscellaneous¶
- Adds logging to server compute endpoint. Includes expression being computed and total time to compute. (#1436)
- Merged the
coreandallconda recipes (#1451). This simplifies the build process and makes it consistent with the singleblazepackage provided by the Anaconda distribution. - Adds a
--yaml-diroption toblaze-serverto indicate the server should load path-basedyamlresources relative to the yaml file’s directory, not the CWD of the process (#1460).
Release 0.9.1¶
| Release: | 0.9.1 |
|---|---|
| Date: | December 17th, 2015 |
New Expressions¶
Improved Expressions¶
New Backends¶
None
Improved Backends¶
- Blaze Server no longer depends on Bokeh for CORS handling, and now uses the flask-cors third-party package (#1378).
Experimental Features¶
None
API Changes¶
None
Bug Fixes¶
- Fixed a
blaze-serverentry point bug regarding an ambiguity between thespider()function and thespidermodule (#1385). - Fixed
blaze.expr.datetime.truncate()handling for the sql backend (#1393). - Fix
blaze.expr.core.isidentical()to check the_hashargsinstead of the_args. This fixes a case that caused objects that hashed the same to not compare equal when somewhere in the tree of_argswas a non hashable structure (#1387). - Fixed a type issue where
datetime - datetime :: datetimeinstead oftimedelta(#1382). - Fixed a bug that caused
coerce()to fail when computing againstColumnElements. This would breakcoercefor many sql operations (#1382). - Fixed reductions over
timedeltareturningfloat(#1382). - Fixed interactive repr for
timedeltanot coercing totimedeltaobjects (#1382). - Fixed weakkeydict cache failures that were causing
.dshapelookups to fail sometimes (#1399). - Fixed relabeling columns over selects by using reconstruct_select (:issue: 1471).
Miscellaneous¶
- Removed support for Spark 1.3 (#1386) based on community consensus.
- Added
blaze.utils.literal_compile()for converting sqlalchemy expressions into sql strings with bind parameters inlined as sql literals.blaze.utils.normalize()now accepts a sqlalchemy selectable and usesliteral_compileto convert into a string first (#1386).
Release 0.9.0¶
| Release: | 0.9.0 |
|---|---|
| Date: | December 17th, 2015 |
New Expressions¶
Improved Expressions¶
New Backends¶
- Initial support for dask.dataframe has been added, see (#1317). Please send feedback via an issue or pull request if we missed any expressions you need.
Improved Backends¶
Blaze Server now supports dynamically adding datasets (#1329).
Two new keyword only arguments are added to
compute()for use when computing against aClientobject:compute_kwargs: This is a dictionary to send to the server to use as keyword arguments when callingcomputeon the server.odo_kwargs: This is a dictionary to send to the server to use as keyword arguments when callingodoon the server.
This extra information is completely optional and will have different meanings based on the backend of the data on the server (#1342).
Can now point
Data()to URLs of CSVs (#1336).
Experimental Features¶
- There is now support for joining tables from multiple sources. This is very experimental right now, so use it at your own risk. It currently only works with things that fit in memory (#1282).
- Foreign columns in database tables that have foreign key relationships can now be accessed with a more concise syntax (#1192).
API Changes¶
- Removed support for Python 2.6 (#1267).
- Removed support for Python 3.3 (#1270).
- When a CSV file consists of all strings, you must pass
has_header=Truewhen using theDataconstructor (#1254). - Comparing
dateanddatetimedatashaped things to the empty string now raises aTypeError(#1308). Likeexpressions behave like a predicate, and operate on columns, rather than performing the selection for you on a table (#1333, #1340).blaze.server.Server.run()no longer retries binding to a new port by default. Also, positional arguments are no longer forwarded to the inner flask app’srunmethod. All keyword arguments not consumed by the blaze serverrunare still forwarded (#1316).Serverrepresents datashapes in a canonical form with consistent linebreaks for use by non-Python clients (#1361).
Bug Fixes¶
- Fixed a bug where
Mergeexpressions would unpack option types in their fields. This could cause you to have a table whereexpr::{a: int32}butexpr.a::?int32. Note that the dotted access is an option (#1262). - Explicitly set
Node.__slots__andExpr.__slots__to(). This ensures instances of slotted subclasses likeJoindo not have a useless empty__dict__attribute (#1274 and #1268). - Fixed a bug that prevented creating a
InteractiveSymbolthat wrappednanif the dshape wasdatetime. This now correctly coerces to NaT (#1272). - Fixed an issue where blaze client/server could not use isin expressions
because the
frozensetfailed to serialize. This also added support for rich serialization over json for things like datetimes (#1255). - Fixed a bug where
lenwould fail on an interactive expression whose resources were sqlalchemy objects (#1273). - Use aliases instead of common table expressions (CTEs) because MySQL doesn’t have CTEs (#1278).
- Fixed a bug where we couldn’t display an empty string identifier in interactive mode (#1279).
- Fixed a bug where comparisons with optionals that should have resulted in optionals did not (#1292).
- Fixed a bug where
Join.schemawould not always be instantiated (#1288). - Fixed a bug where comparisons to a empty string magically converted
the empty string to
None(#1308). - Fix the
retrykwarg to the blaze server. Whenretryis False, an exception is now properly raised if the port is in use. (#1316). - Fixed a bug where leaves that only appeared in the predicate of a selection
would not be in scope in time to compute the predicate. This would cause whole
expressions like
a[a > b]to fail becausebwas not in scope (#1275). - Fix a broken test on machines that don’t allow postgres to read from the local filesystem (#1323).
- Updated a test to reflect changes from odo #366 (#1323).
- Fixed pickling of blaze expressions with interactive symbols (#1319).
- Fixed repring partials in blaze expression to show keyword arguments (#1319).
- Fixed a memory leak that would preserve the lifetime of any blaze expression that had cached an attribute access (#1335).
- Fixed a bug where
common_subexpression()gave the wrong answer (#1325, #1338). BinaryMathoperations without numba installed were failing (#1343).- win32 tests were failing for
hypotandatan2due to slight differences in numpy vs numba implementations of those functions (#1343). - Only start up a
ThreadPoolwhen using the h5py backend (#1347, #1331). - Fix return type for sum and mean reductions whose children have a
Decimaldshape.
Miscellaneous¶
blaze.server.Server.run()now useswarnings.warn()instead ofprintwhen it fails to bind to a port and is retrying (#1316).- Make expressions (subclasses of Expr) weak referencable (#1319).
- Memoize dshape and schema methods (#1319).
- Use
pandas.DataFrame.sort_values()with pandas version >= 0.17.0 (#1321).
Release 0.8.3¶
| Release: | 0.8.3 |
|---|---|
| Date: | September 15, 2015 |
New Expressions¶
Improved Expressions¶
Distinctexpressions now support an on parameter to allow distinct on a subset of columns (#1159)Reductioninstances are now named as their class name if their_childattribute is named'_'(#1198)Joinexpressions now promotes the types of the fields being joined on. This allows us to join things likeint32andint64and have the result be an int64. This also allows us to join any typeawith?a. (#1193, #1218).
New Backends¶
Improved Backends¶
API Changes¶
Serialization format in blaze server is now passed in as a mimetype (#1176)
We only allow and use HTTP
POSTrequests when sending a computation to Blaze server for consistency with the HTTP spec (#1172)Allow
Clientobjects to explicitly disable verification of ssl certificates by passingverify_ssl=False. (#1170)Enable basic auth for the blaze server. The server now accepts an
authorizationkeyword which must be a callable that accepts an object holding the username and password, or None if no auth was given and returns a bool indicating if the request should be allowed.Clientobjects can pass an optionalauthkeyword which should be a tuple of (username, password) to send to the server. (#1175)We now allow
Distinctexpressions onColumnElementto be more general and let things likesa.sql.elements.Labelobjects through (#1212)Methods now take priority over field names when using attribute access for
Fieldinstances to fix a bug that prevented accessing the method at all (#1204). Here’s an example of how this works:>>> from blaze import symbol >>> t = symbol('t', 'var * {max: float64, isin: int64, count: int64}') >>> t['count'].max() t.count.max() >>> t.count() # calls the count method on t t.count() >>> t.count.max() # AttributeError Traceback (most recent call last): ... AttributeError: ...
Bug Fixes¶
- Upgrade versioneer so that our version string is now PEP 440 compliant (#1171)
- Computed columns (e.g., the result of a call to
transform()) can now be accessed via standard attribute access when using the SQL backend (#1201) - Fixed a bug where blaze server was depending on an implementation detail of
CPython regarding
builtins(#1196) - Fixed incorrect SQL generated by count on a subquery (#1202).
- Fixed an
ImportErrorgenerated by an API change in dask. - Fixed an issue where columns were getting trampled if there were column name collisions in a sql join. (#1208)
- Fixed an issue where arithmetic in a Merge expression wouldn’t work
because arithmetic wasn’t defined on
sa.sql.Selectobjects (#1207) - Fixed a bug where the wrong value was being passed into
time()(#1213) - Fixed a bug in sql relabel that prevented relabeling anything that generated a subselect. (#1216)
- Fixed a bug where methods weren’t accessible on fields with the same name (#1204)
- Fixed a bug where optimized expressions going into a pandas group by were incorrectly assigning extra values to the child DataFrame (#1221)
- Fixed a bug where multiple same-named operands caused incorrect scope
to be constructed ultimately resulting in incorrect results on
expressions like
x + x + x(#1227). Thanks to @llllllllll and @jcrist for discussion around solving the issue. - Fixed a bug where
minute()andMinutewere not being exported which made them unusable from the blaze server (#1232). - Fixed a bug where repr was being called on data resources rather than string, which caused massive slowdowns on largish expressions running against blaze server (#1240, #1247).
- Skip a test on Win32 + Python 3.4 and PyTables until this gets sorted out on the library side (#1251).
Release 0.8.1¶
| Release: | 0.8.1 |
|---|---|
| Date: | July 7th, 2015 |
New Expressions¶
- String arithmetic is now possible across the numpy and pandas backends via the
+(concatenation) and*(repeat) operators (#1058). - Datetime arithmetic is now available (#1112).
- Add a
Concatexpression that implements Union-style operations (#1128). - Add a
Coerceexpression that casts expressions to a different datashape. This maps toastypein numpy andcastin SQL (#1137).
Improved Expressions¶
New Backends¶
None
Improved Backends¶
Blaze Server¶
- Tie blueprint registration to data registration (#1061).
- Don’t catch import error when flask doesn’t exist, since blaze does this
in its
__init__.py(#1087). - Multiple serialization formats including JSON, pickle, and msgpack are now available. Additionally, one can add custom serialization formats with this implementation (#1102, #1122).
- Add a
'names'field to the response of thecompute.<format>route for Bokeh compatibility (#1129). - Add cross origin resource sharing for Bokeh compatibility (#1134).
- Add a command line interface (#1115).
- Add a way to tell the blaze server command line interface what to server via a YAML file (#1115).
SQL¶
- Use aliases to allow expressions on the SQL backend that involve a multiple step reduction operation (#1066, #1126).
- Fix unary not operator
~(#1091). - Postgres uses
==to compareNaNso we do it that way as well for the postgresql backend (#1123). - Find table inside non-default schema when serving off a SQLAlchemy
MetaDataobject (#1145).
API Changes¶
Bug Fixes¶
- Handle SQLAlchemy API churn around reference of
ColumnElementobjects in the 1.0.x series (#1071, #1076). - Obscure hashing bug when passing in both a pandas Timestamp and a
datetime.datetimeobject. Both objects hash to the same value but don’t necessarily compare equal; this makes Python call__eq__which caused anEqexpression to be constructed (#1097). - Properly handle
Andexpressions that involve the same field in MongoDB (#1099). - Handle Dask API changes (#1114).
- Use the
datefunction in SQLAlchemy when getting thedateattribute of adatetimedshaped expression. Previously this was calling extract, which is incorrect for the postgres backend (#1120). - Fix API compatibility with different versions of psutil (#1136).
- Use explicit
int64comparisons on Windows, since the default values may be different (#1148). - Fix name attribute propagation in pandas
Seriesobjects (#1152). - Raise a more informative error when trying to subset with an unsupported expression in the MongoDB backend (#1155).
Release 0.7.3¶
- General maturation of many backends through use.
- Renamed
intotoodo
Release 0.7.0¶
- Pull out data migration utilities to
intoproject - Out-of-core CSV support now depends on chunked pandas computation
- h5py and bcolz backends support multi-threading/processing
- Remove
datadirectory includingSQL,HDF5objects. Depend on standard types within other projects instead (e.g.sqlalchemy.Table,h5py.Dataset, ...) - Better support SQL nested queries for complex queries
- Support databases, h5py files, servers as first class datasets
Release 0.6.6¶
- Not intended for public use, mostly for internal build systems
- Bugfix
Release 0.6.5¶
- Improve uri string handling #715
- Various bug fixes #715
Release 0.6.4¶
- Back CSV with
pandas.read_csv. Better performance and more robust unicode support but less robust missing value support (some regressions) #597 - Much improved SQL support #626 #650 #652 #662
- Server supports remote execution of computations, not just indexing #631
- Better PyTables and datetime support #608 #639
- Support SparkSQL #592
Release 0.6.3¶
by takes only two arguments, the grouper and apply child is inferred using common_subexpression
Better handling of pandas Series object
Better printing of empty results in interactive mode
- Regex dispatched resource function bound to Table, e.g.
Table('/path/to/file.csv')
Release 0.6.2¶
Efficient CSV to SQL migration using native tools #454
Dispatched
dropandcreate_indexfunctions #495DPlyr interface at
blaze.api.dplyr. #484- Various bits borrowed from that interface
transformfunction adopted to main namespaceSummaryobject for named reductions- Keyword syntax in
byandmergee.g.by(t, t.col, label=t.col2.max(), label2=t.col2.min())
New Computation Server #527
Better PyTables support #487 #496 #526
Release 0.6.1¶
- More consistent behavior of
into bcolzbackend- Control namespace leakage
Release 0.6¶
- Nearly complete rewrite
- Add abstract table expression system
- Translate expressions onto a variety of backends
- Support Python, NumPy, Pandas, h5py, sqlalchemy, pyspark, PyTables, pymongo
Release 0.5¶
- HDF5 in catalog.
- Reductions like any, all, sum, product, min, max.
- Datetime design and some initial functionality.
- Change how Storage and ddesc works.
- Some preliminary rolling window code.
- Python 3.4 now in the test harness.
Release 0.4.2¶
- Fix bug for compatibility with numba 0.12
- Add sql formats
- Add hdf5 formats
- Add support for numpy ufunc operators
Release 0.4.1¶
- Fix bug with compatibility for numba 0.12
Release 0.4¶
- Split the datashape and blz modules out.
- Add catalog and server for blaze arrays.
- Add remote arrays.
- Add csv and json persistence formats.
- Add python3 support
- Add scidb interface
Release 0.3¶
- Solidifies the execution subsystem around an IR based on the pykit project, as well as a ckernel abstraction at the ABI level.
- Supports ufuncs running on ragged array data.
- Cleans out previous low level data descriptor code, the data descriptor will have a higher level focus.
- Example out of core groupby operation using BLZ.
Release 0.2¶
- Brings in dynd as a required dependency for in-memory data.
Release 0.1¶
- Initial preview release