Question

I cannot find out how to list and print all objects in a workspace. I’d like to see them all and understand what’s going on. For example, ls() gives you 30 objects. How, besides typing them individually, is it possible to display them all. Seems so trivial, the solution will probably quite embarrasing. The closest I’ve come was ls.str() and the idea of looping over the objects.

Edit: This is not for data frames. I have a workspace full of functions, without data, and like to understand which ones reference which etc.

Answer 1

Do you mean ‘display’ in the sense of “for every object in ls(), I want to see what I would see if I typed it into the prompt”? What if you have some matrix that’s 1000×10000 – you still want to print it? I personally like ls.str() – I think it gives a nice concise overview of everything, and handles the case I just mentioned nicely.

However if you want to basically “display” every object in the sense of typing each on the prompt, I’d suggest a loop:

for ( obj in ls() ) { print(get(obj)) }

Since ls() returns a character vector of variable names, I need to use get(obj) which gets the variable whose name is in obj.

You may wish to do a variation of this in order to print the variable name too, e.g.

for ( obj in ls() ) { cat('---',obj,'---\n'); print(get(obj)) }

As an example:

> a <- 1
> b <- LETTERS[1:10]
> c <- data.frame(a=LETTERS[1:10],b=runif(10))
> for ( obj in ls() ) { cat('---',obj,'---\n'); print(get(obj)) }
--- a ---
[1] 1
--- b ---
 [1] "A" "B" "C" "D" "E" "F" "G" "H" "I" "J"
--- c ---
   a         b
1  A 0.1087306
2  B 0.9577797
3  C 0.8995034
4  D 0.1434574
5  E 0.3548047
6  F 0.1950219
7  G 0.1453959
8  H 0.4071727
9  I 0.3324218
10 J 0.4342141

This does have a drawback though – next time you call ls() there’s now an obj in there. I’m sure there’s some workaround though.

Anyhow, I think I still prefer ls.str() for the way it handles big objects (but I work with a lot of huge (millions of elements) matrices, so that’s my preference).