问题
How can we insert a new line when using the function paste() or any function that concatenates strings in R?
There are many web pages on this topic but none answers clearly or gives a solution that works. I precise I don't want to use the function cat, I need to work with string of characters. Here are all my attempts (derived from all the suggestions on from different forum), they all fail...
1st Try: paste()
msg <- "==================================================\n"
msg <- paste(msg, "Var:")
print(msg)
Output:
[1] "==================================================\n Var:"
2nd Try: paste0()
msg <- "==================================================\n"
msg <- paste0(msg, "Var:")
print(msg)
Output:
[1] "==================================================\nVar:"
3rd Try: sep
msg <- "=================================================="
msg <- paste(msg, "Var:", sep = "\n")
print(msg)
Output:
[1] "==================================================\nVar:"
4th Try: sprintf
msg <- sprintf("==================================================\n")
msg <- paste(msg, "Var:")
print(msg)
Output:
[1] "==================================================\nVar:"
I believe I've tried everything I could... If you have an idea?!
回答1:
You could try strsplit
msg <- "==================================================\n"
msg2 <- paste(msg, "Var:")
strsplit(msg2, "\n")[[1]]
# [1] "=================================================="
# [2] " Var:"
This can also be used with noquote if you don't want quotes.
noquote(strsplit(msg2, "\n")[[1]])
# [1] ==================================================
# [2] Var:
This produces virtually the same result as if you were to use print with quote = FALSE
You can also define your own print method
print.myClass <- function(x, ...) strsplit(x, "\n")[[1]]
class(msg2) <- "myClass"
print(msg2)
# [1] "=================================================="
# [2] " Var:"
来源：https://stackoverflow.com/questions/26022378/r-new-line-in-paste-function