In R, I'd like to retrieve a list of global variables at the end of my script and iterate over them. Here is my code
#declare a few sample variables
a<-10
b<-"Hello world"
c<-data.frame()
#get all global variables in script and iterate over them
myGlobals<-objects()
for(i in myGlobals){
print(typeof(i)) #prints 'character'
}
My problem is that typeof(i) always returns character even though variable a and c are not character variables. How can I get the original type of variable inside the for loop?
Answer
You need to use get to obtain the value rather than the character name of the object as returned by ls:
x <- 1L
typeof(ls())
[1] "character"
typeof(get(ls()))
[1] "integer"
Alternatively, for the problem as presented you might want to use eapply:
eapply(.GlobalEnv,typeof)
$x
[1] "integer"
$a
[1] "double"
$b
[1] "character"
$c
[1] "list"