如何将geom_conn_bundle生成的坐标与图顶点名称关联映射？

我正在尝试找到一种方法，将通过geom_conn_bundle生成的坐标与图的顶点名称进行映射。以下是我的示例数据与实现代码：

d1 <- data.frame(from="origin", to=paste("Dept", seq(1,5), sep=""))
d1 <- rbind(d1,c('origin','application'))
d2<-data.frame(from=c('Dept1','Dept2','Dept3','Dept4','Dept5','application','application','application'),to=c('example1@abc.com','example2@abc.com','example3@abc.com','example4@abc.com','example5@abc.com','App1','App2','App3'))
edges <-rbind(d1,d2)
d1<- data.frame(from='origin',to=paste("Dept",seq(1,5),sep=""))
d_1 <- data.frame(from=rep(d1$to,each=5),to=paste(paste('email',seq(1,100),sep=""),'@abc.com',sep=""))
d_1<-sample_n(d_1, 20)

d_2 <- data.frame(from=rep('application',each=5),to=paste('App',seq(1,100),sep=""))
d_2<-sample_n(d_2, 20)


d1 <- rbind(d1,c('origin','application'))

d2<-rbind(d_1,d_2)
edges <-rbind(d1,d2)
all_leaves<- unique(d2$to)

connect<- rbind(
  data.frame(from=sample(head(d_1$to),15,replace=T), to=sample(tail(d_2$to),15,replace=T)),
  data.frame(from=sample(tail(d_1$to),15,replace=T), to=sample(head(d_2$to),15,replace=T)),
  data.frame(from=sample(d_1$to,15,replace=T), to=sample(d_2$to,15,replace=T)),
  data.frame(from=sample(d_1$to,15,replace=T), to=sample(d_2$to,15,replace=T))
)
connect$value <- runif(nrow(connect))
#connect

vertices  <-  data.frame(
  name = unique(c(as.character(edges$from), as.character(edges$to)))
)
vertices$value <-runif(nrow(vertices))
vertices$group <-edges$from[ match( vertices$name, edges$to ) ]

vertices$id <- NA
myleaves <- which(is.na(match(vertices$name, edges$from) ))
nleaves <- length(myleaves)
vertices$id[ myleaves ] <- seq(1:nleaves)
vertices$angle <- 90 - 360 * vertices$id / nleaves

# calculate the alignment of labels: right or left
# If I am on the left part of the plot, my labels have currently an angle < -90
vertices$hjust <- ifelse( vertices$angle < -90, 1, 0)

# flip angle BY to make them readable
vertices$angle <- ifelse(vertices$angle < -90, vertices$angle+180, vertices$angle)

mygraph <- igraph::graph_from_data_frame( edges, vertices=vertices )

# The connection object must refer to the ids of the leaves:
from  <-  match( connect$from, vertices$name)
to  <-  match( connect$to, vertices$name)
options(repr.plot.width=15, repr.plot.height=8)
# Basic usual argument
p<-ggraph(mygraph, layout = 'dendrogram', circular = TRUE) +
  geom_node_point(aes(filter = leaf, x = x*1.05, y=y*1.05,colour=group, size=value, alpha=0.2)) +
  geom_conn_bundle(data = get_con(from = from, to = to), alpha=0.2, colour="skyblue", width=0.9) +
  geom_node_text(aes(x = x*1.1, y=y*1.1, filter = leaf, label=name, angle = angle, hjust=hjust), size=4, alpha=1.5) +

  theme_void() +
  theme(
    legend.position="none",
    plot.margin=unit(c(0,0,0,0),"cm"),
  ) +
 expand_limits(x = c(1, 1), y = c(1, 1))
#expand_limits(x = c(-1.2, 1.2), y = c(-1.2, 1.2))
p
pg <- ggplot_build(p)

我希望获取通过geom_conn_bundle计算出的每个坐标对应的起点和终点顶点名称，这些坐标可通过pg[[1]][[2]]访问。

可以通过以下步骤实现坐标与顶点名称的映射：

• 关联连接数据与坐标数据：pg[[1]][[2]]中的group列对应每条连接的索引，和connect数据框的行索引一一对应，以此作为关联键合并数据。
• 具体代码实现：

# 给connect添加分组列，对应geom_conn_bundle中的group值
connect$group <- seq_len(nrow(connect))

# 提取geom_conn_bundle生成的坐标数据
bundle_coords <- pg[[1]][[2]]

# 合并坐标数据与连接信息，得到带顶点名称的坐标数据集
coords_with_names <- merge(bundle_coords, connect, by = "group")

# 查看结果，每条坐标点都附带对应起点和终点的名称
head(coords_with_names)

• 说明：合并后的数据集包含坐标（x、y）、分组标识、起点名称（from）、终点名称（to）等信息，每条曲线的所有坐标点都会关联到对应的顶点名称，满足后续分析或可视化的需求。

内容的提问来源于stack exchange，提问作者SAL