如何使用visNetwork重现层级树并设置节点层级位置？

尝试使用visNetwork包重现层级树，但无法为节点设置层级位置。以下是我的实现代码：

# Install and load the visNetwork package
install.packages("visNetwork")
library(visNetwork)
# Create nodes data frame
nodes <- data.frame(
  id = 1:7,
  label = c("BLADDER", "TRODELVY", "EV", "NO ADC RECEIVED", "EV", "NO ADC RECEIVED", "TRODELVY "),
  color = c("gray", "red", "blue", "gray", "blue", "gray", "red"),
  shape = "box"
)

# Create edges data frame
edges <- data.frame(
  from = c(1, 1, 2, 2, 3, 3),
  to = c(2, 3, 4, 5, 6, 7)
)

# Create the network visualization
visNetwork(nodes, edges) %>%
  visNodes(shape = "box") %>%
  visOptions(highlightNearest = TRUE, nodesIdSelection = TRUE)%>%
  visPhysics(solver = "hierarchicalRepulsion", 
             forceAtlas2Based = list(gravitationalConstant = -500))

要实现规整的层级树布局，你不需要依赖物理引擎的hierarchicalRepulsion，直接用visNetwork内置的visHierarchicalLayout()函数就能精准控制节点层级：

修改后的代码：

# Install and load the visNetwork package
install.packages("visNetwork")
library(visNetwork)
# Create nodes data frame
nodes <- data.frame(
  id = 1:7,
  label = c("BLADDER", "TRODELVY", "EV", "NO ADC RECEIVED", "EV", "NO ADC RECEIVED", "TRODELVY "),
  color = c("gray", "red", "blue", "gray", "blue", "gray", "red"),
  shape = "box"
)

# Create edges data frame
edges <- data.frame(
  from = c(1, 1, 2, 2, 3, 3),
  to = c(2, 3, 4, 5, 6, 7)
)

# 生成带层级布局的网络图
visNetwork(nodes, edges) %>%
  visNodes(shape = "box") %>%
  visOptions(highlightNearest = TRUE, nodesIdSelection = TRUE) %>%
  visHierarchicalLayout(
    direction = "UD",  # 层级方向：从上到下（可选LR=从左到右）
    sortMethod = "directed",  # 按边的指向自动识别层级
    levelSeparation = 200  # 层级间的间距
  ) %>%
  visPhysics(enabled = FALSE)  # 关闭物理引擎，固定节点位置

关键说明：

• visHierarchicalLayout()是专门为层级树设计的布局函数，能根据边的父子关系自动排列节点；
• 设置sortMethod = "directed"可以确保节点严格按照from->to的关系分布在对应层级；
• 关闭物理引擎避免节点位置被动态调整，保证布局稳定；
• 通过levelSeparation可以调整层级间距，让整体布局更清晰。

内容的提问来源于stack exchange，提问作者firmo23