如何在R语言visNetwork中通过圆角系数设置曲边？

我来帮你搞定这个问题！你之前尝试设置smooth = list(roundness = 0.3)却没生效，核心原因是你用了visHierarchicalLayout()层级布局，它默认会强制边显示为直线，直接覆盖了你在visEdges里的平滑设置。

下面给你两种可行的解决方案：

方案1：保留层级布局，允许自定义平滑边 #

只需要在visHierarchicalLayout()里添加edgeSmooth = "dynamic"参数，让布局尊重你在visEdges中定义的平滑规则，同时明确设置smooth的类型和弯曲度：

library(visNetwork)
nodes <- data.frame(id = 1:3, color = c("blue", "red", "green"))
edges <- data.frame(from = c(1,2,3), to = c(2,3,1))
nodes <- data.frame(nodes, level = edges$from)

visNetwork(nodes, edges, height = "500px", width = "100%") %>% 
  visOptions(highlightNearest = list(enabled = TRUE, degree = 2, hover = TRUE)) %>% 
  visOptions(highlightNearest = FALSE, nodesIdSelection = FALSE, width = 500, height = 500, autoResize = FALSE) %>% 
  # 关键：修改层级布局的edgeSmooth参数，启用自定义平滑
  visHierarchicalLayout(edgeSmooth = "dynamic") %>% 
  visEdges(
    shadow = TRUE, 
    arrows = list(to = list(enabled = TRUE, scaleFactor = 2)), 
    color = list(color = "black", highlight = "red"), 
    smooth = list(
      enabled = TRUE,
      type = "curvedCW", # 可选curvedCCW实现逆时针弯曲
      roundness = 0.3    # 调整这个值改变弯曲程度，0是直线，1是最大弯曲
    )
  )

方案2：更换为非层级布局（如环形布局） #

如果你不需要严格的层级结构，换成circle、random这类布局的话，直接设置smooth参数就能生效，不需要额外调整布局参数：

library(visNetwork)
nodes <- data.frame(id = 1:3, color = c("blue", "red", "green"))
edges <- data.frame(from = c(1,2,3), to = c(2,3,1))
nodes <- data.frame(nodes, level = edges$from)

visNetwork(nodes, edges, height = "500px", width = "100%") %>% 
  visOptions(highlightNearest = list(enabled = TRUE, degree = 2, hover = TRUE)) %>% 
  visOptions(highlightNearest = FALSE, nodesIdSelection = FALSE, width = 500, height = 500, autoResize = FALSE) %>% 
  visLayout(layout = "circle") %>% # 环形布局示例，也可以用其他非层级布局
  visEdges(
    shadow = TRUE, 
    arrows = list(to = list(enabled = TRUE, scaleFactor = 2)), 
    color = list(color = "black", highlight = "red"), 
    smooth = list(roundness = 0.3)
  )

补充说明 #

• roundness的值范围是0到1，值越大弯曲程度越高；
• type = "curvedCW"是顺时针弯曲，curvedCCW是逆时针弯曲，你可以根据需求选择。

内容的提问来源于stack exchange，提问作者Adam Shaw