Rename variable names in dplyr based on vectors new_varname, old_varname [duplicate]

Question

Is there a way "dplyr way" to rename a subset of variables from a data.frame based on variables name translator (vt), a data.frame containing columns with the old and new variable names (old_varname and new_varname respectively). For example:

d <- iris
vt <- data.frame(old_varname=c('Sepal.Length','Petal.Length'),
                  new_varname=c('a','b'))
d <- d %>% rename_( .... )
#In base R code, this would be:
names(d)[names(d) %in% vt$old_varname] <- vt$std_varname

Edit: Further clarification:

• Assume the vector of variables to be translated is very long, so writing the old-new name pairs by hand is not viable
• The variables to be renamed are a subset of total variables, I still want to keep all variables

Answer 1

Try this:

d <- iris
vt <- data.frame(old_varname=c('Sepal.Length','Petal.Length'),
              new_varname=c('a','b'), stringsAsFactors = F)
d.out <- d %>% rename_(.dots = setNames(vt$old_varname, vt$new_varname))

head(d.out)
    a Sepal.Width   b Petal.Width Species
1 5.1         3.5 1.4         0.2  setosa
2 4.9         3.0 1.4         0.2  setosa
3 4.7         3.2 1.3         0.2  setosa
4 4.6         3.1 1.5         0.2  setosa
5 5.0         3.6 1.4         0.2  setosa
6 5.4         3.9 1.7         0.4  setosa

Please note that the first argument to setNames cannot accept factor, so I modify the vt by adding stringsAsFactors = F.

Answer 2

Another way to solve this problem is to unquote a named vector with the new column names as the names and the old column names as the values. Note that I'm using purrr::set_names to make the named vector.

library(tidyverse)
d <- as_tibble(iris)
vt <- tibble(old_varname=c('Sepal.Length','Petal.Length'),
             new_varname=c('a','b'))
d_new_names <- d %>% rename(!!set_names(vt$old_varname, vt$new_varname))
head(d_new_names)