Search code examples
rtidyverser-glue

r - use `glue` to substitute variables in a column with whats in another column


I am trying to keep a data frame were I have a list of messages for the user. I'd like to be able to substitute my variables in my message with what is in the column i am referencing.

For example, this works:

df <- data.frame(id = rep(1:3, each = 3),
                 this = rep(letters[1:3], each = 3),
                 that = rep(letters[24:26], each = 3),
                 foo = rep(c("apple", "pear", "banana"), each = 3))

df %>% mutate(message = glue("{this} is {that}"))

But this does not:


library(tidyverse)
library(glue)

verbiage <- data.frame(id = 1:3,
                       message = c("{this} is {that}", "{foo} is something", "something is {foo}"))

verbiage

df <- data.frame(id = rep(1:3, each = 3),
                 this = rep(letters[1:3], each = 3),
                 that = rep(letters[24:26], each = 3),
                 foo = rep(c("apple", "pear", "banana"), each = 3))

df

df %>% 
  inner_join(verbiage, by = "id") %>% 
  mutate(message = glue(message))

Solution

  • We can use rowwise

    library(glue)
    library(dplyr)
    df %>% 
       inner_join(verbiage, by = "id")  %>%
       rowwise %>% 
       mutate(message = as.character(glue(as.character(message))))
    # A tibble: 9 x 5
    # Rowwise: 
    #     id this  that  foo    message            
    #  <int> <fct> <fct> <fct>  <chr>              
    #1     1 a     x     apple  a is x             
    #2     1 a     x     apple  a is x             
    #3     1 a     x     apple  a is x             
    #4     2 b     y     pear   pear is something  
    #5     2 b     y     pear   pear is something  
    #6     2 b     y     pear   pear is something  
    #7     3 c     z     banana something is banana
    #8     3 c     z     banana something is banana
    #9     3 c     z     banana something is banana