Version 0.6.1 (December 13, 2011)#
New features#
- Can append single rows (as Series) to a DataFrame 
- Add Spearman and Kendall rank correlation options to Series.corr and DataFrame.corr (GH 428) 
- Added - get_valueand- set_valuemethods to Series, DataFrame, and Panel for very low-overhead access (>2x faster in many cases) to scalar elements (GH 437, GH 438).- set_valueis capable of producing an enlarged object.
- Add PyQt table widget to sandbox (GH 435) 
- DataFrame.align can accept Series arguments and an axis option (GH 461) 
- Implement new SparseArray and - SparseListdata structures. SparseSeries now derives from SparseArray (GH 463)
- Implement fast data ranking for Series and DataFrame, fast versions of scipy.stats.rankdata (GH 428) 
- Implement - DataFrame.from_itemsalternate constructor (GH 444)
- DataFrame.convert_objects method for inferring better dtypes for object columns (GH 302) 
- Add rolling_corr_pairwise function for computing Panel of correlation matrices (GH 189) 
- Add margins option to pivot_table for computing subgroup aggregates (GH 114) 
- Add - Series.from_csvfunction (GH 482)
- Can pass DataFrame/DataFrame and DataFrame/Series to rolling_corr/rolling_cov (GH #462) 
- MultiIndex.get_level_values can accept the level name 
Performance improvements#
- Improve memory usage of - DataFrame.describe(do not copy data unnecessarily) (PR #425)
- Optimize scalar value lookups in the general case by 25% or more in Series and DataFrame 
- Fix performance regression in cross-sectional count in DataFrame, affecting DataFrame.dropna speed 
- Column deletion in DataFrame copies no data (computes views on blocks) (GH #158) 
Contributors#
A total of 7 people contributed patches to this release. People with a “+” by their names contributed a patch for the first time.
- Dieter Vandenbussche 
- Fernando Perez + 
- Jev Kuznetsov + 
- Joon Ro 
- Ralph Bean + 
- Wes McKinney 
- Wouter Overmeire