当我尝试将 tibble 转换为树（treedata或phylo）对象时出现错误，即使 tibble 最初是由树生成的。参见示例：
library(ape, quietly = TRUE, warn.conflicts = FALSE)
library(tidytree, quietly = TRUE, warn.conflicts = FALSE)
library(treeio, quietly = TRUE, warn.conflicts = FALSE)
#> treeio v1.14.4 For help: https://yulab-smu.top/treedata-book/
set.seed(2017)
a <- rtree(4) %>% as_tibble() %>% as.data.frame()
#> Warning: Unknown or uninitialised column: `node`.
print(a)
#> parent node branch.length label
#> 1 5 1 0.434905600 t4
#> 2 7 2 0.674331481 t1
#> 3 7 3 0.002020766 t3
#> 4 6 4 0.025093514 t2
#> 5 5 5 NA <NA>
#> 6 5 6 0.472166386 <NA>
#> 7 6 7 0.273833123 <NA>
# ERROR ON BOTH
a %>% as.treedata() #calls treeio:::as.treedata.data.frame which calls treeio:::as.phylo.tbl_df
#> Error in check_edgelist(x): Cannot find root. network is not a tree!
a %>% as.phylo() #calls treeio:::as.phylo.data.frame which is equal to treeio:::as.phylo.tbl_df
#> Error in check_edgelist(x): Cannot find root. network is not a tree!
它要求 'unique(parents[!(parents %in% children)])' 返回一个非零向量，但这与根节点本身的性质相矛盾：
例如 tidytree:::rootnode.tbl_tree 将根定义为具有 parent==node 的节点
由reprex 包（v1.0.0）于 2021-06-04 创建
会话信息sessioninfo::session_info()
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#> tz Etc/UTC
#> date 2021-06-04
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