I have a list called tmp which contains two elements like below.

> tmp
$a
integer(0)

$b
   [1]    1    2    3    4    5    6    7    8    9   10   11   12   13   14   15   16   17   18   19
  [20]   20   21   22   23   24   25   26   27   28   29   30   31   32   33   34   35   36   37   38
  [39]   39   40   41   42   43   44   45   46   47   48   49   50   51   52   53   54   55   56   57
  [58]   58   59   60   61   62   63   64   65   66   67   68   69   70   71   72   73   74   75   76
  [77]   77   78   79   80   81   82   83   84   85   86 ...
[ reached getOption("max.print") -- omitted 386732 entries ]

I would like to create my own text in console using paste() or print() to print all the values like this:

[1] "a contains integer(0)"
[1] "b contains 1, 2, 3, 4, 5, 6, 7, ..., 386732"

(used ... for the convenience but I want all the values to be printed)

What I have tried is

names <- c('a', 'b')
#1
for (p in seq_along(names)) {
  print(paste(names[p], 'contains', as.list(tmp[p])))
}

#2
cat(sprintf("%s contains %s\n", names, tmp))

and the output is

[1] "a contains integer(0)"
[1] "b contains 1:387732"

Does anyone know how I can print the entire list as one? Thank you!

I have a list called tmp which contains two elements like below.

> tmp
$a
integer(0)

$b
   [1]    1    2    3    4    5    6    7    8    9   10   11   12   13   14   15   16   17   18   19
  [20]   20   21   22   23   24   25   26   27   28   29   30   31   32   33   34   35   36   37   38
  [39]   39   40   41   42   43   44   45   46   47   48   49   50   51   52   53   54   55   56   57
  [58]   58   59   60   61   62   63   64   65   66   67   68   69   70   71   72   73   74   75   76
  [77]   77   78   79   80   81   82   83   84   85   86 ...
[ reached getOption("max.print") -- omitted 386732 entries ]

I would like to create my own text in console using paste() or print() to print all the values like this:

[1] "a contains integer(0)"
[1] "b contains 1, 2, 3, 4, 5, 6, 7, ..., 386732"

(used ... for the convenience but I want all the values to be printed)

What I have tried is

names <- c('a', 'b')
#1
for (p in seq_along(names)) {
  print(paste(names[p], 'contains', as.list(tmp[p])))
}

#2
cat(sprintf("%s contains %s\n", names, tmp))

and the output is

[1] "a contains integer(0)"
[1] "b contains 1:387732"

Does anyone know how I can print the entire list as one? Thank you!

• r
• list
• printing
• paste

• 1 Maybe also check out listviewer library(listviewer); jsonedit(temp); – Tim G Commented Mar 28 at 7:42

4 Answers 4

You can use sapply + toString, and then paste the result with its name.

x <- list(a = 0, b = c(1:5))

paste(names(x), "contains", sapply(x, toString))

# or

sprintf("%s contains %s", names(x), sapply(x, toString))

# [1] "a contains 0"
# [2] "b contains 1, 2, 3, 4, 5"

The issue you may be having is that you are trying to print a list element, rather than the underlying vector. Here is a working snippet:

x <- list(a=0, b=c(1:5))

unlist(sapply(names(x), function(y) paste(y, "contains", paste(x[[y]], collapse=","))))

             a                      b 
"a contains 0" "b contains 1,2,3,4,5"

I iterate the names of the input list implicitly using sapply. Then I collapse each list element into a CSV string using paste. Note carefully that I dereference each list element via x[[y]], so that I am working with the underlying vector rather than a list element.

Here's two for-loop variations:

tmp <- list(a=NULL, b=c(0,1,1,2,3,5,8,13))

for (p in 1:length(tmp)) { 
  cat(paste(names(tmp)[p], 'contains'), paste(tmp[[p]], collapse=","))
  cat("\n")
}

a contains 
b contains 0,1,1,2,3,5,8,13

for (p in 1:length(tmp)) { 
  print(paste(names(tmp)[p], 'contains', paste(tmp[[p]], collapse=",")))
}

[1] "a contains "
[1] "b contains 1,1,2,3,5,8,13"

Not exactly the same as what you are after, but should help a bit if you use capture.output + str

> tmp <- list(a = integer(0), b = 1:10)

> capture.output(str(tmp))[-1]
[1] " $ a: int(0) "
[2] " $ b: int [1:10] 1 2 3 4 5 6 7 8 9 10"