Obtaining part of string before question mark

Question

I've got a table of strings like i.e.:

START0001?sthEND1,
START002?sthEND2,
START03?sthEND3,
START4

How could I obtain the table:

START1,
START2,
START3,
START4
?

I can do this with gsub(sub('^([^?]+)*','',napis),"",napis) but there is a problem with "?" sign that stays after all.

Henry Navarro · Accepted Answer · 2017-11-02T11:23:42.850

0

Try this:

y<-"START0001?sthEND1"
x<-unlist(strsplit(y,""))
idx<-which(grepl("\\?",x))
x<-paste0(x[1:(idx-1)],collapse = "")
x<-gsub("0","",x)

edited Nov 02 '17 at 11:23

answered Nov 02 '17 at 11:00

Henry Navarro

Thanks for answer. What if START strings are not of the same lenght? I can do this with regular string, but there is a problem with "?" sign. – Jaroslaw Twarog Nov 02 '17 at 11:10
Look the answer again @JaroslawTwarog – Henry Navarro Nov 02 '17 at 11:23
@JaroslawTwarog, Does it work? – Henry Navarro Nov 06 '17 at 13:38
Works fine, thanks. – Jaroslaw Twarog Nov 08 '17 at 10:04
@JaroslawTwarog So give the answer as right please! – Henry Navarro Nov 08 '17 at 10:04
newstring <- gsub("\\?.*", "", oldstring) I think this should work. – Jaroslaw Twarog Nov 08 '17 at 11:26
@Yes, understand, I refer put an upvote to my answer. – Henry Navarro Nov 08 '17 at 11:27

1 Answers1