CODEWITHSUNDEEP
r
Al14
Al14

Reputation: 1814

avoid non matching IDs

I am subsetting and ordering a dataframe according to an external vector which contains IDs non-matching the col name. How can I avoid the NAs in the final data.frame?

a<-c(2, 4, 6, 6, 8, 10, 12, 13, 14)
b<-c(21:29)
name<-c("O1", "O2", "O3", "O4", "O5","O6", "O7", "O8", "O9")
ID<-rep(c("no","bo", "fo"), each=3)
df<-data.frame(name,ID, a, b)

target<-c("O5","O6", "O7", "O3", "O4", "O1", "O2", "O10", "O11")
    newdf <- df[match(target, df$name),]

   name   ID  a  b
5    O5   bo  8 25
6    O6   bo 10 26
7    O7   fo 12 27
3    O3   no  6 23
4    O4   bo  6 24
1    O1   no  2 21
2    O2   no  4 22
NA   <NA> <NA> NA NA
NA.1 <NA> <NA> NA NA

Upvotes: 1

Views: 54

Answers (1)

akrun
akrun

Reputation: 887501

We can use nomatch=0 in the match. By default, the non matching elements will be occupied by 'NA'. When there is an NA element, it will add an additional NA row for each NA from the match. 

df[match(target, df$name, nomatch=0),]

Or we can use %in% to get the logical index of elements in 'name' that are also in target and use that as row index.

df[df$name %in% target,]

Upvotes: 1

Related Questions