[Pytables-announce] PyTables 0.8.1 released

[Francesc A. <fa...@py...>]

The primary purpose of this release is to incorporate updates to
related to the newly released numarray 1.0. I've taken the opportunity
to backport some improvements added in PyTables 0.9 (in alpha stage)
as well as to fix the known problems

Improvements:

- The logic for computing the buffer sizes has been revamped. As a
  consequence, the performance of writing/reading tables with large
  row sizes has improved by a factor of ten or more, now exceeding 70
  MB/s for writing and 130 MB/s for reading (using compression). See
  http://sf.net/mailarchive/forum.php?thread_id=4963045&forum_id=13760
  for more info.

- The maximum row size for tables has been raised to 512 KB
  (before it was 8 KB, due to some internal limitations)

- Documentation has been improved in minor details. As a result of a
  fix in the underlying documentation system (tbook), chapters start
  now at odd pages, instead of even. So those of you who want to print
  to double side probably will have better luck now when aligning
  pages ;).  Another one is that HTML documentation has improved its
  look as well.

Bug Fixes:

- Indexing of Arrays with list or tuple flavors (#968131)
  When retrieving single elements from an array with 'List' or
  'Tuple' flavors, an error occurred. This has been
  corrected and now you can retrieve fileh.root.array[2] without
  problems for 'List' or 'Tuple' flavored (E, VL)Arrays.
  
- Iterators on Arrays with list or tuple flavors fail (#968132)
  When using iterators with Array objects with 'List' or
  'Tuple' flavors, an error occurred. This has been
  corrected.

- Last Index (-1) of Arrays doesn't work (#968149)
  When accessing to the last element in an Array using the notation
  -1, an empty list (or tuple or array) is returned instead of the
  proper value. This happened in general with all negative
  indices. Fixed.

- Table.read(flavor="List") should return pure lists (#972534)
  However, it used to return a pointer to numarray.records.Record
  instances, as in:

   >>> fileh.root.table.read(1,2,flavor="List") 
    [<numarray.records.Record instance at 0x4128352c>] 
   >>> fileh.root.table.read(1,3,flavor="List") 
    [<numarray.records.Record instance at 0x4128396c>, 
     <numarray.records.Record instance at 0x41283a8c>] 
 
  Now the next records are returned:

   >>> fileh.root.table.read(1,2, flavor=List) 
    [(' ', 1, 1.0)] 
   >>> fileh.root.table.read(1,3, flavor=List) 
    [(' ', 1, 1.0), 
     (' ', 2, 2.0)] 
 
  In addition, when reading a single row of a table, a
  numarray.records.Record pointer was returned:
 
  >>> fileh.root.table[1] 
   <numarray.records.Record instance at 0x4128398c> 
 
  Now, it returns a tuple:

  >>> fileh.root.table[1] 
   (' ', 1, 1.0) 
 
  Which I think is more consistent, and more Pythonic.

- Copy of leaves fails... (#973370)
  Attempting to copy leaves (Table or Array with different flavors) on
  top of themselves caused an internal error in PyTables. This has
  been corrected by silently avoiding the copy and returning the
  original Leaf as a result.

Minor changes:

- When assigning a value to a non-existing field in a table row, now a
  KeyError is raised, instead of the AttributeError that was issued
  before. I think this is more consistent with the type of error.

- Tests have been improved so as to pass the whole suite when compiled
  in 64 bit mode on a Linux/PowerPC machine (namely a dual-G5 Powermac
  running a 64-bit, 2.6.4 Linux kernel and the preview YDL
  distribution for G5, with 64-bit GCC toolchain). Thanks to Ciro
  Cattuto for testing and reporting the modifications that were
  needed.


Let me know of any bugs, suggestions, gripes, kudos, etc. you may
have.

Have fun!

-- 
Francesc Alted