I would like to rename columns that have the following pattern:

x1_test_thing
x2_test_thing

into:

test_thing_1
test_thing_2

Essentially moving the number to the end while removing the string (x) before it.

If a solution using dplyr and using rename_at() could be suggested that would be great.

If there is a better way to do it i'd definitely love to see it.

Thanks!

CodePudding user response：

Using dplyr::rename_at function to rename the name of columns:

1. first parameter is your datafame.

2. second parameter is selecting the columns matching your requirements.

3. third parameter is choosing the function to processing the name of columns, and the parameters of function to processing strings put after comma. For example, gsub is a function to processing strings. Originally, the usage of the function is gsub(x=c("x1_test_thing","x2_test_thing"),pattern = "^.(.)_(test_thing)",replacement = "\\2_\\1"), but the correct usage is gsub,pattern = "^.(.)_(test_thing)",replacement = "\\2_\\1" when you use this function at dplyr::rename_at.

• pattern = "^.(.)_(test_thing)" means using the pair of parentheses to capture the second character, such as "1", and the characters after underline to the end of string, such as "test_thing" ,from the name of columns.

• replacement = "\\2_\\1" means concatenating strings at the second pair of parentheses (test_thing) ,such as "test_thing", a underline"_" ,with strings at the first pair of parentheses (.), such as "1", to get desired output ,and finally replace the name of columns with the string processed.

library(dplyr)

# using test data for example
test <- data.frame(x1_test_thing=c(0),x2_test_thing=c(0))
rename_at(test, vars(contains("test_thing")),gsub,pattern = "^.(.)_(test_thing)",replacement = "\\2_\\1")

CodePudding user response：

We can use readr::parse_number to extract the number from the string.

library(dplyr)

df <- data.frame(x1_test_thing= 1:5, x2_test_thing= 5:1)

df %>%
  rename_with(~paste0('test_thing_', readr::parse_number(.)))

#  test_thing_1 test_thing_2
#1            1            5
#2            2            4
#3            3            3
#4            4            2
#5            5            1

To rename only those column that have 'test_thing' in them -

df %>%
  rename_with(~paste0('test_thing_', readr::parse_number(.)), 
               contains('test_thing'))

In base R,

names(df) <- sub('x(\\d )_.*', 'test_thing_\\1', names(df))
df