Version 0.5.0 (October 24, 2011)¶
New features¶
Added
DataFrame.alignmethod with standard join optionsAdded
parse_datesoption toread_csvandread_tablemethods to optionally try to parse dates in the index columnsAdded
nrows,chunksize, anditeratorarguments toread_csvandread_table. The last two return a newTextParserclass capable of lazily iterating through chunks of a flat file (GH242)Added ability to join on multiple columns in
DataFrame.join(GH214)Added private
_get_duplicatesfunction toIndexfor identifying duplicate values more easily (ENH5c)Added column attribute access to DataFrame.
Added Python tab completion hook for DataFrame columns. (GH233, GH230)
Implemented
Series.describefor Series containing objects (GH241)Added inner join option to
DataFrame.joinwhen joining on key(s) (GH248)Implemented selecting DataFrame columns by passing a list to
__getitem__(GH253)Implemented & and | to intersect / union Index objects, respectively (GH261)
Added
pivot_tableconvenience function to pandas namespace (GH234)Implemented
Panel.rename_axisfunction (GH243)DataFrame will show index level names in console output (GH334)
Implemented
Panel.takeAdded
set_eng_float_formatfor alternate DataFrame floating point string formatting (ENH61)Added convenience
set_indexfunction for creating a DataFrame index from its existing columnsImplemented
groupbyhierarchical index level name (GH223)Added support for different delimiters in
DataFrame.to_csv(GH244)TODO: DOCS ABOUT TAKE METHODS
Performance enhancements¶
VBENCH Major performance improvements in file parsing functions
read_csvandread_tableVBENCH Added Cython function for converting tuples to ndarray very fast. Speeds up many MultiIndex-related operations
VBENCH Refactored merging / joining code into a tidy class and disabled unnecessary computations in the float/object case, thus getting about 10% better performance (GH211)
VBENCH Improved speed of
DataFrame.xson mixed-type DataFrame objects by about 5x, regression from 0.3.0 (GH215)VBENCH With new
DataFrame.alignmethod, speeding up binary operations between differently-indexed DataFrame objects by 10-25%.VBENCH Significantly sped up conversion of nested dict into DataFrame (GH212)
VBENCH Significantly speed up DataFrame
__repr__andcounton large mixed-type DataFrame objects
Contributors¶
A total of 9 people contributed patches to this release. People with a “+” by their names contributed a patch for the first time.
Aman Thakral +
Luca Beltrame +
Nick Pentreath +
Skipper Seabold
Thomas Kluyver +
Wes McKinney
Yaroslav Halchenko +
lodagro +
unknown +