Why my for loop fails?

[Tung]

for (x in c("JP_Employment", "JP_MainJobHours","JP_FullPartTime","JP_JobPay","JP_MainJobEarn")) {
  t.test(table2.11$x, CG_Interview_Pre_1$x, alternative = "two.sided")
}

I need to test these 5 variables. So 5 times together. I tried to do a for loop. But it failed. Can anyone help me?

[nirgrahamuk]

The $x syntax is not going to use the x that is in the for loop scope, but rather will expect to find exactly an x variable in the table to the left of the $ symbol. If you want to use 'x' programatically and evaluate it use the double square brackets operation like in this example. I also show how you can iterate with purrr map rather than for loops.

library(tidyverse)

#example data
(table1 <- filter(iris,Species=="setosa") %>% select(-Species))
(table2 <- filter(iris,Species=="virginica"%>% select(-Species))

(nameset <- names(table1))
  
for (x in nameset) {
  print(x)
  t.test(table1[[x]],
         table2[[x]],
         alternative = "two.sided") %>%
    print
}
  
  #better ?
 (myresults <-  map(nameset,
      ~ t.test(table1[[.x]],
               table2[[.x]],
               alternative = "two.sided")) %>% set_names(nameset))