Trim a string in R

Question

I am trying to isolate a portion of a string in R. The strings have the form ABC_constantStuff_ABC_randomStuff and ABC is what I am trying to extract. ABC is unknown and can be 1-3 characters long. I've been trying grep and gsub but am unsure how to specify my regular expression using

str <- 'GDP\" title=\"GDP - News\"></a>"'
symbol <- gsub(pattern,'',str)

Here GDP is unknown and can be 1-3 characters long, \" title=\" is constant in every string and I would like to remove \" title=\"GDP - News\"></a>"

Thank you for help in advance.

If you're parsing HTML, make sure to read http://stackoverflow.com/a/1732454/16632 — hadley, Feb 08 '13 at 16:41

score 4 · Accepted Answer · answered Feb 08 '13 at 15:00

A simple one is

R> gsub("^([A-Z]*)_.*", "\\1", "ABC_constantStuff_ABC_randomStuff")
[1] "ABC"
R>

which gets all letters up to the first _.

Another one assumming _ is your separator is

R> strsplit( "ABC_constantStuff_ABC_randomStuff", "_")[[1]][c(1,3)]
[1] "ABC" "ABC"
R>

Arun · Answer 2 · 2013-02-08T15:14:04.653

3

Does this help?

> sub("\".*$", "", str)

edited Feb 08 '13 at 15:14

answered Feb 08 '13 at 14:59

Arun

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Trim a string in R

2 Answers2