An interface to Anders Buch's Littlewood-Richardson Calculator lrcalc

[mwhansen]

The attached patch, and spkg implements an interface to Anders Buch's Littlewood-Richardson Calculator lrcalc

The "Littlewood-Richardson Calculator" is a C library for fast
computation of Littlewood-Richardson (LR) coefficients and products of
Schubert polynomials. It handles single LR coefficients, products of
and coproducts of Schur functions, skew Schur functions, and
fusion products. All of the above are achieved by counting LR
(skew)-tableaux (also called Yamanouchi (skew)-tableaux) of
appropriate shape and content by iterating through them.
Additionally, lrcalc handles products of Schubert polynomials.

The web page of lrcalc is: http://math.rutgers.edu/~asbuch/lrcalc/

Here is a short extract of the doc:

EXAMPLES::

    sage: import sage.libs.lrcalc.lrcalc as lrcalc

Compute a single Littlewood-Richardson coefficient::

    sage: lrcalc.lrcoef([3,2,1],[2,1],[2,1])              #optional - lrcalc
    2

Compute a product of Schur functions; return the coefficients in the Schur expansion::

    sage: lrcalc.mult([2,1], [2,1])                       #optional - lrcalc
    {[3, 3]: 1, [4, 2]: 1, [3, 1, 1, 1]: 1, [4, 1, 1]: 1, [2, 2, 2]: 1, [3, 2, 1]: 2, [2, 2, 1, 1]: 1}

Add optional package attachment: lrcalc-1.1.6beta.spkg

Apply: attachment: trac_10333-lrcalc-final.patch

Making lrcalc into a standard package in the next Sage release is the topic of the followup ticket: #11563

CC: @sagetrac-sage-combinat @asbuch @saliola

Component: packages: optional

Keywords: spkg package, Schubert calculus, Littlewood-Richardson, days30

Author: Mike Hansen, Anders Buch, Nicolas M. Thiéry, Anne Schilling

Reviewer: Nicolas M. Thiéry, Anne Schilling

Merged: sage-5.0.beta2

Issue created by migration from https://trac.sagemath.org/ticket/10333

[anneschilling]

comment:3

Together with Anders Buch, I went through this patch at Sage Days 30 and checked all functionalities. We added further doctests and also access to fusion coefficients (which was not in the previous version of this patch).

From the mathematical point of view, I give this a positive review. Could someone please do a quick technical review of the patch?

Thanks!

Anne

Apply: trac_10333-lrcalc-final.patch

[anneschilling]

Reviewer: Anne Schilling

[anneschilling]

Changed keywords from none to spkg package, Schubert calculus, Littlewood-Richardson

[anneschilling]

comment:5

I fixed some more typos and omissions on the doctest.

Positive review on the mathematics and features.

Could someone complete the technical review?

Cheers,

Anne

[anneschilling]

Changed keywords from spkg package, Schubert calculus, Littlewood-Richardson to spkg package, Schubert calculus, Littlewood-Richardson, days30

[fchapoton]

comment:7

for the bot:

Apply: trac_10333-lrcalc-final.patch

[anneschilling]

Changed author from Mike Hansen to Mike Hansen, Anders Buch, Nicolas Thiery, Anne Schilling

[anneschilling]

Changed reviewer from Anne Schilling to Nicolas Thiery, Anne Schilling

[nthiery]

comment:9

Hi,

I used the occasion to do something I had promissed Anders a while ago: namely to add a standard GNU build system (autoconf/automake) to the original lrcalc sources. With this, the SPKG becomes trivial. I'll upload shortly a preversion of it. If Anders agrees with the changes, and once he will have done an official release, I'll upload a final version of the spkg.

Mike: could you review now the three little files: SPKG.txt, spkg-install and spkg-check? Those are unlikely to change.

[nthiery]

comment:12

I fixed a couple tiny typos in lrcalc.pyx, and uploaded an updated patch. For me this part is good to go.

[nthiery]

comment:13

According to the vote on http://groups.google.com/group/sage-devel/browse_thread/thread/2e7114375f6f88a5/, there is a consensus on making lrcalc a standard package, after a one release probation period in order to follow the official rule. See: #11563

[anneschilling]

comment:14

Can we now set a positive review on this patch?

Anne

[nathanncohen]

comment:15

(pending an answer, if no one knows whether this ticket should be reviewed...)

[anneschilling]

comment:16

Replying to @nathanncohen:

(pending an answer, if no one knows whether this ticket should be reviewed...)

As far as I know, everything is fine with the ticket except that Nicolas is waiting for confirmation from Anders Buch about the spkg. Nicolas, is everything ok now on this front?

Anne

[jdemeyer]

comment:32

One more thing: the spkg should follow the format of http://sagemath.org/doc/developer/producing_spkgs.html#the-file-spkg-txt. In particular, the Changelog should be formatted differently.

[nthiery]

Final spkg

[nthiery]

comment:33

Attachment: lrcalc-1.1.6beta.spkg.gz

Replying to @jdemeyer:

One more thing: the spkg should follow the format of http://sagemath.org/doc/developer/producing_spkgs.html#the-file-spkg-txt. In particular, the Changelog should be formatted differently.

Oops. Thanks for spotting this. I updated the spkg accordingly. Do you mind reviewing the new SPKG.txt?

[jdemeyer]

comment:34

Actually, the documentation still doesn't work:

/mnt/usb1/scratch/jdemeyer/merger/sage-5.0.beta2/devel/sage/doc/en/reference/sage/libs/lrcalc/lrcalc.rst:7: WARNING: autodoc can't import/find module 'sage.libs.lrcalc.lrcalc', it reported error: "No module named lrcalc", please check your spelling and sys.path
/mnt/usb1/scratch/jdemeyer/merger/sage-5.0.beta2/local/lib/python2.7/site-packages/sage/misc/edit_module.py:docstring of sage.misc.edit_module.edit_devel:14: WARNING: Inline interpreted text or phrase reference start-string without end-string.

[nthiery]

comment:35

Replying to @jdemeyer:

Actually, the documentation still doesn't work:

/mnt/usb1/scratch/jdemeyer/merger/sage-5.0.beta2/devel/sage/doc/en/reference/sage/libs/lrcalc/lrcalc.rst:7: WARNING: autodoc can't import/find module 'sage.libs.lrcalc.lrcalc', it reported error: "No module named lrcalc", please check your spelling and sys.path
/mnt/usb1/scratch/jdemeyer/merger/sage-5.0.beta2/local/lib/python2.7/site-packages/sage/misc/edit_module.py:docstring of sage.misc.edit_module.edit_devel:14: WARNING: Inline interpreted text or phrase reference start-string without end-string.

I don't understand. Why is this lrcalc.rst file generated, whereas no such file is generated for, e.g. the analoguous sage/numerical/backends/coin_backend.pyx?

[jhpalmieri]

comment:36

When I click on attachment: trac_10333-lrcalc-final.patch, it still has a line adding sage/libs/lrcalc/lrcalc to doc/en/reference/libs.rst. That's presumably the problem.

[anneschilling]

comment:37

Replying to @jhpalmieri:

When I click on attachment: trac_10333-lrcalc-final.patch, it still has a line adding sage/libs/lrcalc/lrcalc to doc/en/reference/libs.rst. That's presumably the problem.

Nicolas, could you please also put the updated patch on the sage-combinat server.

Thanks,

Anne

[nthiery]

comment:38

Attachment: trac_10333-lrcalc-final.patch.gz

Replying to @jhpalmieri:

When I click on attachment: trac_10333-lrcalc-final.patch, it still has a line adding sage/libs/lrcalc/lrcalc to doc/en/reference/libs.rst. That's presumably the problem.

What's the heck? How did I do this?

Oh well; fixed. Thanks for spotting it!

[nthiery]

comment:39

Nicolas, could you please also put the updated patch on the sage-combinat server.

Done.

[nthiery]

comment:40

Jeroen: I let you set back the positive review. Sorry for all the back and forth.

[anneschilling]

comment:41

Replying to @nthiery:

Jeroen: I let you set back the positive review. Sorry for all the back and forth.

The line referring to doc/en/reference/libs.rst seems to be gone now, so I set this back to positive review. Hopefully it will work now!

Anne

[jdemeyer]

Merged: sage-5.0.beta2

[nthiery]

comment:43

Yippee :-)

Thanks everyone!

[jdemeyer]

Changed author from Mike Hansen, Anders Buch, Nicolas Thiery, Anne Schilling to Mike Hansen, Anders Buch, Nicolas M. Thiéry, Anne Schilling

[jdemeyer]

Changed reviewer from Nicolas Thiery, Anne Schilling to Nicolas M. Thiéry, Anne Schilling