Replace a string of characters to " " in a data frame column using R function

Question

I want to replace everything after the first _ in data77298$SAMPLE.CODE to " ", such that I get levels to be GSM2048265, GSM2048266 etc.,

Is it possible using a single command to change all strings after the underscore to null?

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score 1 · Answer 1 · answered Jun 29 '16 at 18:29

1

you can do it by gsub

my_string<-c("GSM2048265_Somet_323_h4554ing_here","GSM2048266_sometwewe_sdsd_hing_here")
gsub("\\_.*","",my_string)
[1] "GSM2048265" "GSM2048266"

answered Jun 29 '16 at 18:29

user5249203

score 0 · Answer 2 · answered Jun 29 '16 at 19:12

0

How about:

library(stringr)
my_string<-c("GSM2048265_1_2_£_$_F_CA","GSM2048266_aasv_vaerv_vasd", "GSM2048266_arvqb_oyor_1234")
word(my_string, 1, sep = "_")

answered Jun 29 '16 at 19:12

thepule

2 Answers2