|
From: | address@hidden |
Subject: | [igraph] Question about the functions induced.subgraph() and clusters() |
Date: | Fri, 21 Mar 2014 22:37:30 +0800 |
Hi
Is the question below out of that the vertice id has been changed in
induced.subgraph()?
If I want to generate a subgraph which contains all the vertices and just
delete the edges to make the vertices, which were meant to be delete, to be
isolate?
best
Xueming
address@hidden 发件人: address@hidden
发送时间: 2014-03-21 22:00
收件人: igraph-help
主题: Question about the functions induced.subgraph() and
clusters() Hi!
It is
known to us that the maximal weakly connected component of a connected nework is
itself. Just like the code below shows that the elements of Siz_wcc never
change.
ga <-
erdos.renyi.game(1000, 1500, type = "gnm", directed=TRUE);
Siz_wcc <- rep(0,10)
for(i in 1:10)
{
wcca <- clusters(ga, mode="weak")
largest_wcc_va <- which(wcca$membership == which.max(wcca$csize))
Siz_wcc[i] <- length(largest_wcc_va)
ga
<- induced.subgraph(ga, largest_wcc_va, impl="copy_and_delete")
}
> Siz_wcc
[1] 936 936 936 936 936 936 936 936 936 936 Given
two networks ga and gb, if network ga is exactly the same with network gb, then
the elements in Siz_wcca and Siz_wccb are also expected to be invariant. But
Siz_wcca and Siz_wccb decrease to 1 in the end. How could this happen?
gb <-
erdos.renyi.game(1000, 1500, type = "gnm", directed=TRUE);
ga <-
gb
Siz_wcca <-
rep(0,10)
Siz_wccb <-
rep(0,10)
for(i in 1:10)
{
wcca <- clusters(ga, mode="weak")
largest_wcc_va <- which(wcca$membership == which.max(wcca$csize))
Siz_wcca[i] <- length(largest_wcc_va)
gb
<- induced.subgraph(gb, largest_wcc_va, impl="copy_and_delete")
wccb <- clusters(gb, mode="weak")
largest_wcc_vb <- which(wccb$membership == which.max(wccb$csize))
Siz_wccb[i] <- length(largest_wcc_vb)
ga
<- induced.subgraph(ga, largest_wcc_vb, impl="copy_and_delete")
}
> Siz_wcca
[1] 933 854 756 615 331 3 1
1 1 1
> Siz_wccb
[1] 933 845 722 521 46 1 1
1 1 1 best
Xueming
address@hidden |
[Prev in Thread] | Current Thread | [Next in Thread] |