[R] escaping backslash in a string
Gabor Grothendieck
ggrothendieck at myway.com
Mon Nov 29 21:47:50 CET 2004
Dan Lipsitt <danlipsitt <at> gmail.com> writes:
:
: I have it working now, I think. Since it's going into a regular
: expression, I have to escape each of the escape characters, resulting
: in four backslashes altogether:
:
: > sub("[.]", "x", "a.b")
: [1] "axb"
: > sub("[.]", "\.", "a.b")
: [1] "a.b"
: > sub("[.]", "\\.", "a.b")
: [1] "a.b"
: > sub("[.]", "\\\.", "a.b")
: [1] "a.b"
: > sub("[.]", "\\\\.", "a.b")
: [1] "a\\.b"
: > cat(sub("[.]", "\\\\.", "a.b"))
: a\.b>
:
: or
:
: > cat(sub("\\.", "\\\\.", "a.b"))
: a\.b>
:
You can use \134 in place of the double backslash
if that makes more sense to you.
Another possibility is to create a variable
backslash <- "\\"
and paste together each string in terms of that variable.
Also its sometimes helpful to use nchar(s) on string s
just to check how many characters it has.
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