r - 取消列表后的向量不同长度

Question

我正在尝试将列表转换为向量，以便我可以将其附加到数据帧，但它会引发错误。取消列表后，它变得更短，我不知道为什么。

谢谢，非常感谢任何帮助。

> mongo_jr$last_state <- unlist(last_state)
Error in `$<-.data.frame`(`*tmp*`, "last_state", value = c("created",  : 
  replacement has 203819 rows, data has 203823

> str(last_state)
List of 203823

x <- unlist(last_state)

> str(x)
 chr [1:203819] "created" "created" "created" "created" "created" "created" "created" "created" ...

Answer 1

原来有些值是空的

transition_duration[sapply(last_state, is.null)] <- NA
mongo_jr$last_state <- unlist(last_state)

工作。