如何删除数据帧中的子元素以绘制R中的网络？

我想用R绘制一个网络。然而，问题是，我的数据框（其中包含关系数据）也包含子对象的子对象。如下所示：

parent <- c("A","A","A","B","B","E")
child <-  c("B","C","D","C","D","D")
df <- data.frame(parent,child)

---

使用igraph来确定个体之间的路径如何，如果有多个路径，请删除该连接

library(igraph)
parent <- c("A","A","A","B","B","E")
child <-  c("B","C","D","C","D","D")
df <- data.frame(parent,child)
net <- graph_from_data_frame(df,directed = T)
df <- df[apply(df,1,function(x){length(all_simple_paths(net,x[1],x[2]))}) == 1,]
df
  parent child
1      A     B
4      B     C
5      B     D
6      E     D

库（igraph）
父级这是一种
dplyr
解决方案：

library(dplyr)

# get data
parent <- c("A","A","A","B","B","E")
child <-  c("B","C","D","C","D","D")
df <- data.frame(parent,child, stringsAsFactors = FALSE)

# remove rows that are not directly related
new_df <- anti_join(df,
          left_join(df,df,by=c("child"="parent")) %>% 
  select(parent,child=child.y) %>% 
  na.omit()) 

new_df
  parent child
1      A     B
2      B     C
3      B     D
4      E     D

库（dplyr）
#获取数据
家长我理解的对吗？您想保留家长中不在孩子中的所有项目？不，最后一部分只是一个想法，最终没有成功。我想从df中删除不直接相关的行。例如，保留第一行（AB），但删除第二行（AC）和第三行（AD），因为A与C和D没有直接关系，而只是通过B。因为B（即A的子级）也将C和D作为子级。这是分层模型的一个前提条件，因此a与C和D没有直接关系。如果它这么简单，那就太酷了！但是，我收到了一条错误消息：“as.igraph.vs（graph，from）中的错误：无效的顶点名称”：（抱歉，我遗漏了一个重要步骤。谢谢！！！效果非常好！我从未想过这一点。我尝试了一些数据，但速度一点也不慢。所以对我来说，这很好。
`%notin%` <- Negate(`%in%`)
i <- nrow(df)
y <- list()
z <- list()
j <- 1
while (i > 0) {
  v <- unique(df$parent[!(df$parent %in% df$child)]) # find mismatch (only in parent, not in child)
  df <- df %>% filter(parent %notin% v)
  print(v)
  y[[j]] <- v
  z[[j]] <- df
  i = nrow(df)
  j = j+1
}

library(igraph)
parent <- c("A","A","A","B","B","E")
child <-  c("B","C","D","C","D","D")
df <- data.frame(parent,child)
net <- graph_from_data_frame(df,directed = T)
df <- df[apply(df,1,function(x){length(all_simple_paths(net,x[1],x[2]))}) == 1,]
df
  parent child
1      A     B
4      B     C
5      B     D
6      E     D

library(dplyr)

# get data
parent <- c("A","A","A","B","B","E")
child <-  c("B","C","D","C","D","D")
df <- data.frame(parent,child, stringsAsFactors = FALSE)

# remove rows that are not directly related
new_df <- anti_join(df,
          left_join(df,df,by=c("child"="parent")) %>% 
  select(parent,child=child.y) %>% 
  na.omit()) 

new_df
  parent child
1      A     B
2      B     C
3      B     D
4      E     D