Got it !

I knew nothing about all this, sorry :-)

I was just growing impatient because I only wrote the interface
between GLPK/Coin and Sage to add new functions to the Graph class,
whose docstrings I am currently writing... I already wrote :

def min_dominating_set(g, value_only=False):
def min_independant_dominating_set(g, value_only=False):
def min_vertex_cover(g,value_only=False):
def max_matching(g,value_only=False, use_edge_labels=True):
def max_flow(g,x,y,value_only=True,integer=False,
use_edge_labels=True):
def min_edge_cut(g,s,t,value_only=True,use_edge_labels=True):
def min_vertex_cut(g,s,t,value_only=True):
def edge_connectivity(g,value_only=True,use_edge_labels=True):
def vertex_connectivity(g,value_only=True):
def coloring(g,k=None):

and I think they may be pretty useful in the standard Sage.. ( it is
pretty easy to write them through LP, none of them is longer than 30
lines, but try to do it without... :-) )

Robert : I'll give a look to pymprog immediately, just to see what I
could add to what is already written, or if they are just ages in
advance.. But we had to write some meta-LP class to be able to use
indifferently GLPK, Coin, and CPLEX anyway... ;-)

Thank you all again !

Nathann

On Aug 1, 3:24 pm, David Joyner <[email protected]> wrote:
> I think Nathann Cohen has done a very valuable service with the GLPK and
> COIN-OR-related packages.
>
> That said, I have a "point of order" question. Is is true or false that the
> process for a package to become standard we
> (1) use trac to do nomination, testing, and acceptance as an optional
> package,
> (2) someone (William say) posts the spkg 
> tohttp://www.sagemath.org/packages/optional/,
> (3) after a period of a few months, voting is done for making it standard.
>
> In any case, I vote +1 for Nathann's GLPK spkg being moved to optional
> and the currently posted GLPK spkg on experimental removed, with the
> idea that it be proposed for inclusion as a standard package.
>
> If the above process is correct then there is nothing more to say.
> If not, I think  someone (not me) look into this PyGLPK (I am
> not an OR person and have never heard of this before). By
> compare, I mean, look at the license, compare Nathann's wrappers and
> docstrings to PyGLPK's, etc. Maybe there are other wrappers
> on the internet (I have not done a google search, just mentioning
> possibilities here.)
>
> On Sat, Aug 1, 2009 at 8:55 AM, Robert<[email protected]> wrote:
>
> > I'd like LPs, too, of course.
>
> > By the way, do you know of the projecthttp://pymprog.sourceforge.net/
> > that wraps GLPK with it's modelling language in python? Using PyGLPK,
> > as an additional layer, I'm pretty sure there is some relevant code
> > there.
>
> > On Aug 1, 12:46 pm, Carlo Hamalainen <[email protected]>
> > wrote:
> >> On Sat, Aug 1, 2009 at 9:41 AM, Nathann Cohen<[email protected]> 
> >> wrote:
> >> > Are you interested by LP features in Sage with GLPK as the native
> >> > solver ? ( The others would have to be optional packages but we
> >> > thought it would be smart to have a native one ).
>
> >> Yes, especially if it can be used to speed up the graph colouring code
> >> in some cases (at the moment it uses my C++ dlx solver but I'm sure
> >> that LP etc could be useful in some other cases).
>
> >> --
> >> Carlo Hamalainenhttp://carlo-hamalainen.net
--~--~---------~--~----~------------~-------~--~----~
To post to this group, send an email to [email protected]
To unsubscribe from this group, send an email to 
[email protected]
For more options, visit this group at http://groups.google.com/group/sage-devel
URLs: http://www.sagemath.org
-~----------~----~----~----~------~----~------~--~---

Reply via email to