Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
388 views
in Technique[技术] by (71.8m points)

r - Filter a column which contains several keywords

I am trying to filter a column which contains several keywords (in this example dog and cat) but I am having problems as only the first element is being used.

id <- c(1:7)
type <- c("dog1","dog2" ,"cat1","cat2","zebra1", "parrot5", "elephant15")
filter1 <- c("dog","cat")
df1 <- data.frame(id,type)
dfilter <- df1[grep(filter1,df1$type),]
dfilter

I would be grateful for your help.

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Answer

0 votes
by (71.8m points)

grep can use | as an or, so why not paste your filters together with | as a separator:

dfilter <- df1[grep(paste0(filter1, collapse = "|"), df1$type),]

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

2.1m questions

2.1m answers

60 comments

57.0k users

...