showing vertex labels inside vertexes only - r

Question

I have this data frame:
dput(df2)
structure(list(Receiver = structure(c(4L, 3L, 2L, 1L), .Label = c("Australia",
"United Arab Emirates", "United Kingdom", "United States of America"
), class = "factor"), Sender = structure(c(1L, 1L, 1L, 1L), .Label = "United States of America", class = "factor")), .Names = c("Receiver",
"Sender"), row.names = c(NA, -4L), class = "data.frame")
I would like to draw and igraph as this:
library(igraph)
g<-graph.data.frame(df2)
plot(g, layout = layout.kamada.kawai, vertex.label = V(g)$name,
vertex.label.color= "red", edge.arrow.size=0.8,
edge.curved=T, edge.label.color="white",
edge.label.cex=0.8,vertex.shape="circle",edge.color="pink",
vertex.color="lightblue", asp=0, margin=0)
I would like to show vertex lables inside the verexes, without increasing the size of the vertexes. Any ideas how I can do this?

Answer 1

You can do something like this before the call plot:
V(g)$label.cex <- 0.5
But why not to use a shortcut of the names?
V(g)$name<-c('USA','UK','UAE','Aus')
dat <- structure(list(Receiver = structure(c(4L, 3L, 2L, 1L), .Label = c("Australia",
"United Arab \nEmirates", "United \nKingdom", "United \nStates of \nAmerica"
), class = "factor"), Sender = structure(c(1L, 1L, 1L, 1L), .Label = "United \nStates of \nAmerica", class = "factor")), .Names = c("Receiver",
"Sender"), row.names = c(NA, -4L), class = "data.frame")
library(igraph)
g<-graph.data.frame(dat)
V(g)$label.cex <- 0.6
plot(g, layout = layout.kamada.kawai, vertex.label = V(g)$name,
vertex.label.color= "red", edge.arrow.size=0.8,
edge.curved=T, edge.label.color="white",
edge.label.cex=0.8,vertex.shape="circle",edge.color="pink",
vertex.color="lightblue", asp=0, margin=0)

Answer 2

The following might help.
# size the network nodes based on their centrality
deg = igraph::degree(graph = g, v = V(g), mode = "all", loops = TRUE, normalized = FALSE);
igraph::V(g)$size = deg*3;
# set the label size based on the node size
igraph::V(g)$label.cex = igraph::V(g)$size/max(igraph::V(g)$size);