Printing messages in R

[Rachelly]

I want to print a message containing a few variables in a line, and some text in between. Is it possible to do it elegantly, as in C?

The closest solution I found is

x<-1 y<-2 print(c("x=",x,"y=",y)) [1] "x=" "1" "y=" "2"

But this is not so elegant, since the variables are not really characters and there are quote marks all arounf. Printing a list doesn't give the desirable results either:

print(list("x=",x,"y=",y)) [[1]] [1] "x=" [[2]] [1] 1 [[3]] [1] "y=" [[4]] [1] 2

Thanks, Rachelly.

[renozao]

You can use the function message:

x <- 1
y <- 'aas'
message('the variable x contains the value ', x,  ' and y = ', y)

You can also use it in combination with the function str_out in pkgmaker:

> x <- setNames(1:10, letters[1:10])
> message('My variable x contains: ', str_out(x) )
My variable x contains: 1L, 2L, ..., 10L
> message('My variable x contains: ', str_out(x, 5) )
My variable x contains: 1L, 2L, 3L, 4L, ..., 10L
> message('My variable x contains: ', str_out(x, Inf) )
My variable x contains: 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L, 10L

If you want to debug only, the function str is convenient, especially for -- not too long -- list objects. It directly prints in stderr:

> x <- as.list(setNames(1:10, letters[1:10]))
> str(x)
List of 10
 $ a: int 1
 $ b: int 2
 $ c: int 3
 $ d: int 4
 $ e: int 5
 $ f: int 6
 $ g: int 7
 $ h: int 8
 $ i: int 9
 $ j: int 10