Split comma-separated strings in a column into separate rows
(6个答案)
4年前关闭。
我有一个这样的数据框:
> df <- data.frame(Column1=c("id1", "id2", "id3"), Column2=c("text1,text2,text3", "text4", "text5,text6"), Column3=c("text7", "text8,text9,text10,text11", "text12,text13"))
> df
Column1 Column2 Column3
1 id1 text1,text2,text3 text7
2 id2 text4 text8,text9,text10,text11
3 id3 text5,text6 text12,text13
如何将其转换为这种格式?
Column1 variable value
1 id1 Column2 text1
2 id1 Column2 text2
3 id1 Column2 text3
4 id2 Column2 text4
5 id3 Column2 text5
6 id3 Column2 text6
7 id1 Column3 text7
8 id2 Column3 text8
9 id2 Column3 text9
10 id2 Column3 text10
11 id2 Column3 text11
12 id3 Column3 text12
13 id3 Column3 text13
我想第一步是对数据帧
melt()
(顺便说一句,我应该担心该警告吗?):
> library(reshape2)
> mdf <- melt(df, id.vars="Column1", measure.vars=c("Column2", "Column3"))
> mdf
Column1 variable value
1 id1 Column2 text1,text2,text3
2 id2 Column2 text4
3 id3 Column2 text5,text6
4 id1 Column3 text7
5 id2 Column3 text8,text9,text10,text11
6 id3 Column3 text12,text13
Warning message:
attributes are not identical across measure variables; they will be dropped
然后我基本上需要``strsplit()`'value'列并相应地复制行,但是我想不出一种方法来做到这一点。
> strsplit(mdf$value, ",")
[[1]]
[1] "text1" "text2" "text3"
[[2]]
[1] "text4"
[[3]]
[1] "text5" "text6"
[[4]]
[1] "text7"
[[5]]
[1] "text8" "text9" "text10" "text11"
[[6]]
[1] "text12" "text13"
任何帮助表示赞赏!谢谢。
您可以尝试:
library(reshape2)
https://gist.github.com/mrdwab/11380733中的
cSplit
cSplit(melt(df, id.vars="Column1"), "value", ",", "long")
# Column1 variable value
# 1: id1 Column2 text1
# 2: id1 Column2 text2
# 3: id1 Column2 text3
# 4: id2 Column2 text4
# 5: id3 Column2 text5
# 6: id3 Column2 text6
# 7: id1 Column3 text7
# 8: id2 Column3 text8
# 9: id2 Column3 text9
#10: id2 Column3 text10
#11: id2 Column3 text11
#12: id3 Column3 text12
#13: id3 Column3 text13
或者,如果您想坚持使用CRAN软件包中提供的功能,请执行以下操作:
library(reshape2)
library(splitstackshape)
library(dplyr)
select(na.omit(concat.split.multiple(melt(df, id.vars="Column1"), split.col="value", sep=",", direction="long")), -time)
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