reduce_nodes_to_focus: Reduces the number of nodes in a network to those which are...
In GarrettLab/INApreliminary: Impact Network Analysis

Description Usage Arguments Details Examples

There is the option to select all nodes linked to the set of key nodes within a certain number of steps, or only in one direction

1	reduce_nodes_to_focus(startmat, maxdist, keynodes, tofrom)

`startmat`	the starting adjacency matrix (NOT an igraph object), to be reduced
`maxdist`	the greatest distance (in terms of the number of links traversed) at which a node is considered connected to the key nodes
`keynodes`	the set of key nodes (e.g., c(1,5,9))
`tofrom`	choice between keeping nodes that are (1) linked towards the key nodes, 'to', (2) linked away from the key nodes, 'from', or (3) either to or from, 'either'

Created 2020-05-29

j <- matrix(rbinom(n=100,p=0.1,size=1),nrow=10)
diag(j) <- 0
jnames <- letters[1:10]
library(igraph)
ji <- graph_from_adjacency_matrix(j)
V(ji)$names <- jnames
plot.igraph(ji, vertex.label=V(ji)$names, vertex.color='light green', main='Starting matrix')

jout <- reduce_nodes_to_focus(startmat=j, maxdist=2, keynodes=c(1,5), tofrom='to')
jouti <- graph_from_adjacency_matrix(jout$outmat)
V(jouti)$names <- jnames[jout$keepers]
plot(jouti, vertex.label=V(jouti)$names, vertex.color='light green', main='2 steps TO key nodes 1 and 5')

jout2 <- reduce_nodes_to_focus(startmat=j, maxdist=2, keynodes=c(1,5), tofrom='from')
jout2i <- graph_from_adjacency_matrix(jout2$outmat)
V(jout2i)$names <- jnames[jout2$keepers]
plot(jout2i, vertex.label=V(jout2i)$names, vertex.color='light green', main='2 steps FROM key nodes 1 and 5')

jout3 <- reduce_nodes_to_focus(startmat=j, maxdist=2, keynodes=c(1,5), tofrom='either')
jout3i <- graph_from_adjacency_matrix(jout3$outmat)
V(jout3i)$names <- jnames[jout3$keepers]
plot(jout3i, vertex.label=V(jout3i)$names, vertex.color='light green', main='2 steps TO OR FROM key nodes 1 and 5')