R help - Apr 2012 - Add attributes to igraph vector by name, not index

Hi, 
So I've been figuring out how to use igraph in R and like it for it's
speed
and simplicity. Now I have a graph built from an edgelist where vectors have
a $name attribute.  I have another dataframe with attributes tied to a
vector ID, which is the same as the $name attribute of vectors represented
in the graph.  

How can I iterate over the graph by V(g)$name and do set.vector.attributes
for the other attributes in the vector dataframe?  Of course, the edgelist
for the graph contains each vector zero or many times and they are not
sorted in the same order as the vector dataframe.  It's a large bit of data:
about 20m edges and 3m vectors. I can't do this by hand.

Perhaps the answer is something like,
by V(g)[]$name in g  {
  i=get.index(V(g)$name)
  if (V(g)[1]$name == dataframe$ID)  {
     V(g)[1]$newattribute1 <- dataframe$attribute1
     V(g)[1]$newattribute2 <- dataframe$attribute2
     V(g)[1]$newattribute3 <- dataframe$attribute3
   }
}

 R,
CW Dillon


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Hi,

you can iterate over the vertices, but it'll be probably slow. The
best solution is to create the graph directly  from the data frame(s)
containing all structure and attribute data. See the
graph.data.frame() function for this.

Btw. it might be worth to post your igraph related questions to the
igraph-help mailing list if you don't get an answer here, (sadly) I am
not reading R-help frequently any more. See http://igraph.sf.net.

Best,
Gabor

On Mon, Apr 23, 2012 at 6:26 AM, cwdillon <cwdillon at gmail.com>
wrote:
> Hi,
> So I've been figuring out how to use igraph in R and like it for
it's speed
> and simplicity. Now I have a graph built from an edgelist where vectors
have
> a $name attribute. ?I have another dataframe with attributes tied to a
> vector ID, which is the same as the $name attribute of vectors represented
> in the graph.
>
> How can I iterate over the graph by V(g)$name and do set.vector.attributes
> for the other attributes in the vector dataframe? ?Of course, the edgelist
> for the graph contains each vector zero or many times and they are not
> sorted in the same order as the vector dataframe. ?It's a large bit of
data:
> about 20m edges and 3m vectors. I can't do this by hand.
>
> Perhaps the answer is something like,
> by V(g)[]$name in g ?{
> ?i=get.index(V(g)$name)
> ?if (V(g)[1]$name == dataframe$ID) ?{
> ? ? V(g)[1]$newattribute1 <- dataframe$attribute1
> ? ? V(g)[1]$newattribute2 <- dataframe$attribute2
> ? ? V(g)[1]$newattribute3 <- dataframe$attribute3
> ? }
> }
>
> ?R,
> CW Dillon
>
>
> --
> View this message in context:
http://r.789695.n4.nabble.com/Add-attributes-to-igraph-vector-by-name-not-index-tp4580032p4580032.html
> Sent from the R help mailing list archive at Nabble.com.
>
> ______________________________________________
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> PLEASE do read the posting guide
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-- 
Gabor Csardi <csardi at rmki.kfki.hu>? ?? MTA KFKI RMKI