R 中的 VisNetwork：调整边的长度

Question

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Is there a way to adjust the length of the edges in VisNetwork so that they are overall a bit longer? Some arrows are a bit hard to see right now especially with the thicker edges.

This is my edge list and nodes list

nodes_t <- structure(list(ahaid = c("6140002", "6140005", "6140007", "6140008", 
"6140010", "6140011", "6140012", "6140013", "6140016", "6140017", 
"6140065", "6140080", "6140090", "6140215", "6140255", "6140270", 
"6140310", "6140420", "6140428", "6140430", "6140465", "6140583", 
"6140620", "6140630", "6140690", "6140780", "6140850", "6140900", 
"6140923", "6140980", "6141010", "6141020", "6141095", "6141110", 
"6141130", "6141170", "6141300", "6141355", "6141395", "6141410", 
"6141430", "6141450", "6141500", "6141530", "6141570", "6141630", 
"6141640", "6141660", "6141705", "6141720", "6141890", "6141900", 
"6141940", "6141955", "6142000", "6142200", "6142280", "6142350"
), weight = c(129L, 67L, 72L, 111L, 193L, 56L, 32L, 601L, 406L, 
151L, 19L, 56L, 25L, 1909L, 22L, 6L, 38L, 6L, 264L, 1416L, 169L, 
133L, 98L, 87L, 387L, 53L, 63L, 101L, 91L, 32L, 11L, 55L, 456L, 
34L, 225L, 62L, 31L, 158L, 185L, 24L, 6L, 43L, 47L, 112L, 93L, 
94L, 12L, 46L, 175L, 161L, 30L, 452L, 234L, 379L, 86L, 19L, 85L, 
135L)), row.names = c(NA, -58L), class = "data.frame")

edges_t <- structure(list(from = c("6140002", "6140008", "6140010", "6140012", 
"6140013", "6140013", "6140013", "6140016", "6140017", "6140080", 
"6140215", "6140215", "6140215", "6140215", "6140215", "6140215", 
"6140215", "6140215", "6140215", "6140215", "6140215", "6140215", 
"6140428", "6140430", "6140430", "6140430", "6140923", "6141020", 
"6141095", "6141095", "6141170", "6141660", "6141940"), to = c("6140430", 
"6141095", "6140215", "6140430", "6140630", "6141450", "6141720", 
"6140215", "6140690", "6140215", "6140310", "6140428", "6140430", 
"6140583", "6140690", "6141095", "6141130", "6141395", "6141530", 
"6141630", "6141900", "6142000", "6140690", "6140850", "6141530", 
"6141900", "6141130", "6141955", "6141300", "6142350", "6141355", 
"6141955", "6141955"), weight = c(19L, 22L, 7L, 8L, 9L, 17L, 
9L, 15L, 19L, 12L, 22L, 7L, 27L, 90L, 14L, 20L, 13L, 32L, 9L, 
11L, 34L, 8L, 7L, 11L, 17L, 16L, 6L, 16L, 7L, 5L, 10L, 17L, 18L
)), row.names = c(NA, -33L), class = "data.frame")

This is my code

vis.nodes <- nodes_t
vis.links <- edges_t
vis.nodes$borderWidth <- 2 
vis.nodes <- vis.nodes %>% mutate(size = weight/16)

vis.links$width <- 1+edges_t$weight/4 
vis.links$arrows <- "to" 

library('visNetwork') 
p <- visNetwork(vis.nodes, vis.links, width="400%", height="1600px")

Answer 1

You could use the visEdges function with argument length to change the length of the edges. Since I can't reproduce your plot, I created a reproducible example:

library(visNetwork)
library(dplyr)
# Data
nodes <- data.frame(id = 1:2)
edges <- data.frame(from = 1, to = 2)

# Plot with length 100
visNetwork(nodes, edges) %>%
  visEdges(arrows = 'to', length = 100) 

# Plot with length 400
visNetwork(nodes, edges) %>%
  visEdges(arrows = 'to', length = 400) 

^{Created on 2022-12-18 with reprex v2.0.2}

As you can see the first plot has an edge length of 100 pixels and the second plot has an edge length of 400 pixels.

---

If you want to have variable lengths, you could add an variable length to your edge dataframe like this:

library(visNetwork)
library(dplyr)
# Data
nodes <- data.frame(id = 1:2)
edges <- data.frame(from = 1, to = 2, length = c(100, 400))

# Plot
visNetwork(nodes, edges) %>%
  visEdges(arrows = "to")

^{Created on 2022-12-18 with reprex v2.0.2}