ggnetwork图不能准确地用节点颜色绘制值

这个问题的解决方法是使用ggraph包，它是ggplot2的扩展，并提供了绘制网络图的功能。首先，需要将数据转换为适合ggraph的格式，然后使用scale_color_continuous函数来绘制节点颜色，例如：

library(ggraph)
library(tidygraph)
library(igraph)

# Convert data to tidygraph format
nodes <- data.frame(id = c("A", "B", "C", "D", "E"),
                    value = c(5, 10, 15, 20, 25))
edges <- data.frame(from = c("A", "B", "D", "E", "C", "C"),
                    to = c("B", "C", "E", "A", "D", "E"))
graph <- tbl_graph(nodes = nodes, edges = edges)

# Plot the network with ggraph
ggraph(graph) +
  geom_edge_link() +
  geom_node_point(aes(fill = value), size = 6) +
  scale_color_continuous(low = "blue", high = "red") +
  theme_void()

在这个例子中，节点的value列用于定义颜色，scale_color_continuous函数将该值映射到蓝色到红色的颜色字典。这样就可以用正确的颜色绘制节点，而不会出现ggnetwork包的问题。