Music21

A new release of music21 focusing on Speed and Stability improvements.

Biggest improvement: Streams are now cached on disk after a parse. The first parse of a file will take the same amount of time as before (actually 10-15% slower), but after the first parse, subsequent parses will take 1/10th the time as before. This should be a great savings for software that parses the same files more than once (not necessarily in the same session). This speed improvement comes from two related improvements:

1) Memory footprint of music21 is greatly reduced due to the use of Python **slots** on many frequently created objects that are rarely edited or expanded by users. (Thanks Josiah!)

2) FreezeThaw works well to store or recall the current state of any stream on disk.

Moved from GoogleCode to GitHub (in case you hadn't noticed).

Improvements to Braille processing (Thanks to Mario Lang) and the Vexflow (thanks "Shimpe")

Better handling of local corpora and the Core corpus (and better docs).

Clearer documentation on how to contribute to music21. (Thanks Carol Willing)

Lilypond output now gets the version of lilypond directly.

BETA: work on automatic chord reduction is ongoing. Please let us know if you want to test anything.

Security improvements in a few places.

Added support for Vibraphone in instruments (thanks Chris Culy) and initial support for tablature six-line staves (thanks metalmike).

Lots of bug fixes and improvements (mainly Josiah's great work under the hood). Thanks also to the NEH, the Digging into Data Challenge, the Seaver Foundation, and MIT for support of the project.

In the three months since v. 1.6 some good changes and improvements have been introduced. We focused primarily on stabilizing features that were already in music21 in some form but were too experimental to advertise widely.

A noCorpus version of music21 has also been released, the first since v.1.0. This version can be used in pure Free/Libre projects since files that were licensed for music21 only or non-commercial use have been removed. If you are not sure which version to download, definitely get the full version. But maintainers of Debian Linux and others can update to 1.7 noCorpus.

Music21 v 1.7 (actually 1.7.1) will be the last version to support Python 2.6. Python 2.7 is over three years old and is supported by other flavors of Python including Jython (which skipped 2.6), PyPy, IronPython and is an easy upgrade for Python on Windows. Mac users have had 2.7 since Mountain Lion and we're happy to report that with Mavericks being free and supporting systems that can run Snow Leopard, we're happy to be able to use this opportunity to take advantage of the latest features and start a roadmap to supporting Python 3.3 as well. This is also the last release to use SVN. We are moving to GitHub. Updates soon.

The most important improvement for users is a much improved system of metadata searching (thanks to Josiah Oberholtzer). See:

http://web.mit.edu/music21/doc/usersGuide/usersGuide_11_corpusSearching.html

for more details. LocalCorpus objects are elevated to equal status as the Core corpus so you can now build searchable indexes on any data you have and find the file you want much faster. Try corpus.search('haydn') and read the docs above to see what's possible.

Among the other 150+ changes since 1.6 include:
- Chord.inversion(2) will take a root position chord and put it in second inversion. (this is a change of behavior from before, where .inversion(2) would specify that the chord was in second inversion and override default inversion reporting (for things like Jazz 6 chords). To get the old behavior, use .inversion(2, transposeOnSet=False)
- Fixes for abc parsing (N.B. the next version will rename the "abc" module to "abcNotation" to avoid the occasional name clash with the python AbstractBaseClass (abc) module).
- Stream.getElementsByOffset(4.0) can now find a zero-length object at 4.0 -- bug fix.
- Many modules are now packages (Stream, for instance). This should not affect your code. Existing packages with X/base.py can now find their files in X/**init**.py. Again, this should not affect your code.
- Page break support in Lilypond.
- MIDI translate works better with instruments (thanks to Christopher Antilla)
- Improvements to Braille Music Code output (thanks to Mario Lang; more to come)
- Bug fixes in measure copying involving pivot chords and secondary dominants in RomanText
- Roman numerals for VII, VI, viio/vii, vi/vio in minor are made more robust. It6, Ger65, Fr43, are now supported.
- Many many many bug fixes. Thanks to community help!

Thanks as always to the NEH, Digging into Data program, the Seaver Institute, and MIT for their support of the project.