[Coin-discuss] Sparse Cholesky factorization routines

[Matthew Saltzman]

On Fri, 9 Mar 2007, Andreas Waechter wrote:

> Hi Brian,
>
> We have started to use MUMPS (http://graal.ens-lyon.fr/MUMPS/) as a "free" 
> large-scale linear solver in Ipopt.  I haven't included the interface yet in 
> the official release, but I'm planning to do that soon (when I get some 
> time).  The plan is to have a ThirdParty/Mumps directory, into which a user 
> will have to download the source code and then the COIN configure and 
> Makefile stuff will make sure it is properly compiled.  MUMPS is written 
> Fortran 90, so one would need such a compiler (it works with gfortran).
>
> MUMPS is pulic domain - here here license:
>
> This version of MUMPS is provided to you free of charge. It is public domain, 
> based on public domain software developed during the Esprit IV European 
> project PARASOL (1996-1999) by CERFACS, ENSEEIHT-IRIT and RAL. Since this 
> first public domain version in 1999, the developments are supported by 
> CERFACS, ENSEEIHT-IRIT, and INRIA.
>
> Main contributors are Patrick Amestoy, Iain Duff, Abdou Guermouche, Jacko 
> Koster, Jean-Yves L'Excellent, and Stephane Pralet.
>
> Up-to-date copies of the MUMPS package can be obtained from the Web pages 
> http://www.enseeiht.fr/apo/MUMPS/ or http://graal.ens-lyon.fr/MUMPS
>
> THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED OR 
> IMPLIED. ANY USE IS AT YOUR OWN RISK.
>
>
> My guess is that it is compatible with the CLP, but I don't know for sure. 
> Does anyone else on the mailing list know...?

Placing intellectual property in the public domain means giving up *all*
copyrights.  Public-domain code can be used by anyone for any purpose, so 
it is certainly compatible with any OSS license.  It can also be rolled 
into proprietary software.

Note that the OSS license comaptibility issue only affects redistributors, 
not end users.  An end user can take COIN-OR code and any available other 
code and compile and link them, as long as they don't redistribute the 
results.  This is what end users do with the OSI and commercial or GPL 
solvers, but we can't distribute binaries linked with either, although we 
could redistribute the GPL solvers in an "aggregation".  It's also what 
Ipopt does with Cholesky solvers.

As MUMPS is in the public domain, we could distribute Ipopt binaries 
linked with MUMPS with no problem.


>
> Cheers,
>
> Andreas
>
>
> On Thu, 8 Mar 2007, Brian Borchers wrote:
>
>> 
>> It seems to me that many of the COIN-OR projects currently use (or could
>> make use) of sparse Cholesky and/or sparse LU factorization routines.
>> For some future work in CSDP, I'd like to use such a library- in particular
>> I need a Sparse Cholesky factorization routine together with a reasonable
>> ordering heuristic.
>> 
>> It would certainly be nice if there were such a package as part of COIN,
>> or at least available under the CPL.  Short of that, which of the available
>> packages are licensed in ways that are compatible with the CPL?  What has
>> worked best for other COIN projects?
>> 
>> 
>>                         - Brian
>> _______________________________________________
>> Coin-discuss mailing list
>> Coin-discuss at list.coin-or.org
>> http://list.coin-or.org/mailman/listinfo/coin-discuss
>> 
> _______________________________________________
> Coin-discuss mailing list
> Coin-discuss at list.coin-or.org
> http://list.coin-or.org/mailman/listinfo/coin-discuss
>

-- 
 		Matthew Saltzman

Clemson University Math Sciences
mjs AT clemson DOT edu
http://www.math.clemson.edu/~mjs