Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.soft-sys.math.mathematica > #16703

Re: Combinatorica versus new graphs in V8

Show all headers | View raw

Many thanks Murray,

It is a pity.

I think that WRI could (and should)  have adopted a different approach to
migrate Combinatorica to the kernel. I suppose that there are many user
applications which make intensive use of Combinatorica. That is, at least,
in my case. And now, what?

E. Martin-Serrano.

-----Mensaje original-----
De: Murray Eisenberg [mailto:murray@math.umass.edu] 
Enviado el: jueves, 27 de marzo de 2014 10:00
Para: mathgroup@smc.vnet.net
Asunto: Re: Combinatorica versus new graphs in V8

I believe there's NO way to implement multiple edges in a System`Graph
object. In fact, you undoubtedly saw, when you tried, the error message:

  Graph::supp: Mixed graphs and multigraphs are not supported.

Moving the functionality of the graph-theoretic functions from the
Combinatorica add-on to the kernel has been a slow process over several
versions of Mathematica and evidently is not yet complete.

We can only hope that the next version of Mathematica, already documented in
preliminary form at

  http://reference.wolfram.com/language/

will allow multiple edges at long last.

On Mar 26, 2014, at 3:23 AM, E. Martin-Serrano
<eMartinSerrano@telefonica.net> wrote:

> Hi,
>
> I am unable to see how to  implement multi edge graphs for pairs of 
> vertices in V8.
>
> With the =91Combinatorica=92 package this was easy to do as in
>
> << Combinatorica`
>
> g = Combinatorica`Graph[{{{1, 2}}, {{2, 3}}, {{2, 3}}, {{2, 3}} , {{2, 
> 3}}}, {{{0, 0}}, {{1, 1}}, {{2, 0}}}]
>
> ShowGraph[g]
>
> Here I have three =91{2,3}=92 concurrent edges for the  vertices pair 
> {2,3}
>
> The following should be equivalent for the V8  kernel implementation 
> of graphs
>
> System`Graph[{UndirectedEdge[1,2], UndirectedEdge[2,3], 
> UndirectedEdge[2,3], UndirectedEdge[2,3], UndirectedEdge[2,3]},
>
> VertexCoordinates -> {{0, 0}, {1, 1}, {2, 0}}]
>
> But the multiple edges feature does not work in the way it did in
> =91Combinatorica=92 (It does not work in any way).
>
> Please, could anyone say what I am missing here?
>
>
> E. Martin
>
>
>
> __________________________________________
>
> This e-mail and the documents attached are confidential and intended 
> solely for the addressee; it may also be privileged. If you receive 
> this e-mail in error, please notify the sender immediately and destroy 
> it. As its integrity cannot be secured on the Internet, no sender's 
> liability can be triggered for the message content. Although the 
> sender endeavors to maintain a computer virus-free network,  he/she 
> does not warrant that this transmission is virus-free and  will not be 
> liable for any damages resulting from any virus transmitted.
>
> Este mensaje y los ficheros adjuntos pueden contener informaci=F3n 
> confidencial destinada solamente a la(s) persona(s) mencionadas 
> anteriormente y su contenido puede estar protegido por secreto 
> profesional y en cualquier caso el mensaje en su totalidad est=E1  
> amparado y protegido por la legislaci=F3n vigente que preserva el 
> secreto de las comunicaciones, y por la legislaci=F3n de protecci=F3n 
> de datos de car=E1cter personal. Si usted recibe este correo 
> electr=F3nico por error, gracias por informar  inmediatamente al 
> remitente y destruir el mensaje. Al no estar asegurada la integridad de
este mensaje sobre la red, el remitente no se hace responsable por su
contenido.
> Su contenido no constituye ning=FAn  compromiso para el remitente, 
> salvo ratificaci=F3n escrita por ambas partes.  Aunque se esfuerza al 
> m=E1ximo por mantener su red libre de virus, el emisor  no puede 
> garantizar nada al respecto y no ser=E1 responsable de cualesquiera 
> da=F1os que puedan resultar de una transmisi=F3n de virus.
>
>
>

Murray Eisenberg                                murray@math.umass.edu
Mathematics & Statistics Dept.      
Lederle Graduate Research Tower      phone 240 246-7240 (H)
University of Massachusetts               
710 North Pleasant Street                
Amherst, MA 01003-9305

Back to comp.soft-sys.math.mathematica | Previous | Next | Find similar

Thread

Re: Combinatorica versus new graphs in V8 "E. Martin-Serrano" <eMartinSerrano@telefonica.net> - 2014-03-28 07:32 +0000

csiph-web