How to replace '(' , ')' using sub in R?

Question

How to replace ( , ) using sub in R ?

Let define x as :

x="abc(def"

then when I try to replace ( by something else the error occur :

sub("(","",x)

the error is :

'Missing ')''

Answer 1

As Kohske said you need double escape, but you can also use the argument fixed=TRUE:

sub("\\(","",x)
sub("(","",x,fixed=TRUE)

Both give you:

[1] "abcdef"

Answer 2

You need escape:

> sub("\\(", "@", x)
[1] "abc@def"