how to replace or remove a part of string?

[YANGHONG]

hi everyone!
some strings in a column have some characters i do not needed.
like apple(china), water (japan), cake(Britain).
i use function---
mutate_at("column name" , str_replace , "(china)" , "" )

but the outcome is apple()
how can i remove () ?
or do you have any better solution? and explain to me, please!

[FJCC]

Parentheses are special characters in regular expression so you have to escape them with back slashes to have them be interpreted as literal parentheses.

library(tidyverse)
#> Warning: package 'tibble' was built under R version 4.1.2
DF <- data.frame(Things=c("apple(china)", "water(japan)", 
                          "cake(britain)"))

DF <- DF |> mutate(Things = str_remove(Things, "\\(.+\\)"))
DF
#>   Things
#> 1  apple
#> 2  water
#> 3   cake

^{Created on 2022-06-04 by the reprex package (v2.0.1)}

[YANGHONG]

thanks a lot, i have resolved this issue.
using a function below

mutate(column_name = str_remove(colunm_name , "\（.+\）"))

would you explain what ".+" mean in "\（.+\）"?
i consider ".+" means every character in parentheses, it is right?

[FJCC]

The .+ is a "regular expression", a kind of advanced wild card. Regular expressions are commonly used in R and other programming languages for matching text. There are many online tutorials and it would be useful for you to study them at some point. The . in the expression means "any character" and the "+" means "one or more". Together they mean "one or more of any character".

[YANGHONG]

got it!
thanks a lot.