Map differing length variables to one data frame - r

Question

Suppose I have to following data
specialty <- c("Primary Care", "Internal Medicine Subspecialties" ,
"Pediatric subspecialties","Surgical subspecialties", "Emergency
Medicine","All other specialties", "No Medical specialty")
test <- c(23,43,67,77,54)
dfTEST <- data.frame(test)
dfTEST<- t(dfTEST)
colnames(dfTEST) <- c(1,2,4,5,7)
> dfTEST
1 2 4 5 7
test 23 43 67 77 54
Note that my dfTest has 5 variables that skip numbers. I need to create a data frame that maps these colname numbers (1,2,4,5,7) to the specialty. Specialty is 7 strings that are in coordination to the dfTest colnames. Meaning dfTest 2 = "Internal Medicine Subspecialties" and dfTest 4 ="surgical subspecialties and so on. Below is a snippet of what I am looking to achieve, but I am stumped on how to go about it. I need it to be flexible so that no matter what the numbers in the colnames are, the code will still work. Any ideas?? Thanks!!
> dfTEST
1 2 4 5 7
test 23 43 67 77 54
added "primary care" "internal" ...

Answer 1

This here should solve your problem.
library(dplyr)
specialty_lookup <- data.frame(specialty = c("Primary Care",
"Internal Medicine Subspecialties",
"Pediatric subspecialties",
"Surgical subspecialties",
"Emergency Medicine",
"All other specialties",
"No Medical specialty"),
test = 1:7,
stringsAsFactors = F)
data <- data.frame(code = c(23,43,67,77,54),
test = c(1,2,4,5,7))
data <- data %>%
left_join(specialty_lookup)
data_wide <- data %>%
select(-test) %>%
t() %>%
data.frame()
colnames(data_wide) <- data$test
data_wide
But you should question yourself if this is really the format you want your data to have. From the little I could see of your problem, the following format would be more adequate:
library(dplyr)
specialty_lookup <- data.frame(specialty = c("Primary Care",
"Internal Medicine Subspecialties",
"Pediatric subspecialties",
"Surgical subspecialties",
"Emergency Medicine",
"All other specialties",
"No Medical specialty"),
test = 1:7, stringsAsFactors = F)
data <- data.frame(code = c(23,43,67,77,54),
test = c(1,2,4,5,7))
data <- data %>%
left_join(specialty_lookup)
data

Answer 2

Hope this helps:
# get the indexes of correspondent specialties
ids <- as.integer(colnames(dfTEST))
dfTEST<- as.data.frame(t(dfTEST))
dfTEST$added <- specialty[ids]
dfTEST<- t(dfTEST)
The output:
> dfTEST
1 2 4
test "23" "43" "67"
added "Primary Care" "Internal Medicine Subspecialties" "Surgical subspecialties"
5 7
test "77" "54"
added "Emergency \n Medicine" "No Medical specialty"