r - Replace two dots in a string with gsub

Question

I'm trying to use the following code to replace two dots for only one:

test<-"test..1"
gsub("\\..", ".", test, fixed=TRUE)

and getting:

[1] "test..1"

I tried several combinations of escape strings, including brackets [] with no success.
What am I doing wrong?

Answer 1

如果要使用fixed = TRUE，请使用（未解释的）字符.：

> gsub("..", ".", test, fixed = TRUE)

否则，在正则表达式 ( fixed = FALSE) 中，.具有特殊含义（任何字符），因此您需要在其前面加上反斜杠以表示“点字符”：

> gsub("\\.\\.", ".", test)
> gsub("\\.{2}", ".", test)