Hi,
[replying on the list]
On 11/22/09 12:58 AM, jiabao xu wrote:
> Hi Seth Falcon,
> thanks for your reply .G1 and G2 are parts of G.and union(G1,G2)
is
> G,If i know the G and G2 ,how to get G1.I am sorry for that i
didn't
> describle clear in the last email.
Hmm, I'm still a bit confused. Do you know that G1 and G2 are
disjoint?
I don't think there is currently a set difference type operations in
the
graph package which might be what you want.
You can find the nodes as:
g1_nodes = setdiff(nodes(G), nodes(G2)) # these will be the G1
nodes
Then perhaps you can just do subGraph(G, g1_nodes)
Hope that helps some.
+ seth
>
> On Sun, Nov 22, 2009 at 12:11 PM, Seth Falcon <sfalcon at="" fhcrc.org=""> <mailto:sfalcon at="" fhcrc.org="">> wrote:
>
> Hi Jiabao,
>
>
> On 11/20/09 11:26 PM, jiabao xu wrote:
>
> hello,everyone:
> I have two graphs: G1(V,E) ,G2(V2,E2) (V2?V,E2?E),how to got
the
> G(V1,E1)
> ,G1?G2=G,V1?V2=V,E1?E2=E.
>
>
> The graph package has intersection() and union() functions that
may
> give you what you want.
>
> If not, perhaps you can give a more detailed example for what
you
> want. In particular, I'm not sure I understand your notation.
> Looks to me like you have defined G2 such that V2 is a subset
of V
> and E2 a subset of E and G1 is (V, E). So then union(G1, G2) is
> just G1?
>
> + seth
>
>
--
Seth Falcon
Program in Computational Biology | Fred Hutchinson Cancer Research
Center