I\'m working on R on a graph and I\'d like to have a hierarchical plot, based on the values in the vector S (a value for each node).
lay2 <- layout_with_sugi
I believe that layout_with_sugiyama
is working just fine,
but you may be misinterpreting the output. Since you do
not provide any data, I will illustrate with some randomly
generated data.
library(igraph)
set.seed(1234)
grafo = erdos.renyi.game(162, 0.03)
lay2 <- layout_with_sugiyama(grafo, attributes="all",
hgap=10, vgap=10)
plot(lay2$extd_graph, vertex.label.cex=0.5, vertex.size=9)
I think the source of your question is the fact that the nodes are a bit crowded together in the horizontal direction. But that should be expected. Let's analyze the layout, starting with the easy part, the vertical direction.
table(lay2$layout[,2])
1 11 21 31 41
24 82 42 13 1
You can see that vgap worked. The spacing is 10 units apart. The second line up (y=11) has 82 nodes. Unless the nodes are tiny, 82 nodes on a single, horizontal line will overlap. But aren't they supposed to have spacing of at least 10? They do! Let's look at that second line.
sort(lay2$layout[lay2$layout[,2]==11,1])
[1] -25 -15 -5 5 15 25 35 45 55 65 75 85 95 105 115 125 135 230
[19] 240 260 270 280 290 300 310 320 330 340 350 360 370 380 390 400 410 420
[37] 430 440 450 460 470 480 490 500 510 520 530 540 550 560 570 580 590 600
[55] 610 620 630 640 655 665 675 685 695 720 730 740 750 760 770 780 790 800
[73] 810 820 830 840 850 860 870 880 890 910
Looking at the whole graph, there is a slightly broader range.
range(lay2$layout[,1])
[1] -65 910
None of the numbers are less that 10 apart - as requested. hgap worked too!
However, what happens when you try to plot that? If you read the part of the
?igraph.plotting
help page that refers to the parameter rescale
,
you will see:
rescale:
Logical constant, whether to rescale the coordinates to the [-1,1]x-1,1 interval. Defaults to TRUE, the layout will be rescaled.
So the layout will be rescaled to a range of -1,1 and then plotted. Scaled or not, you need to fit 82 nodes in a single, horizontal row, so it is very difficult to avoid overlapping nodes.