Is there a way to view a list

You can also use a package called listviewer

library(listviewer)
jsonedit( myList )

I use str to see the structure of any object, especially complex list's

Rstudio shows you the structure by clicking at the blue arrow in the data-window:

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If you have a really large list, you can look at part of it using

str(myList, max.level=1)

(If you don't feel like typing out the second argument, it can be written as max=1 since there are no other arguments that start with max.)

I do this often enough that I have an alias in my .Rprofile for it:

str1 <- function(x, ...) str(x, max.level=1, ...)

And a couple others that limit the printed output (see example(str) for an example of using list.len):

strl <- function(x, len=10L, ...) str(x, list.len=len, ...)  # lowercase L in the func name
str1l <- function(x, len=10L, ...) str(x, max.level=1, list.len=len, ...)

Here's a few ways to look at a list:

Look at one element of a list:

myList[[1]]

Look at the head of one element of a list:

head(myList[[1]])

See the elements that are in a list neatly:

summary(myList)

See the structure of a list (more in depth):

str(myList)

Alternatively, as suggested above you could make a custom print method as such:

printList <- function(list) {

  for (item in 1:length(list)) {

    print(head(list[[item]]))

  }
}

The above will print out the head of each item in the list.

Tags:

List

R