I want to set 2 Console output in the if statement: one is the paste() function and sencond is unique values from one of the column

if (x<= 0) {
Paste("Negative"),
unique(data$category)
}

CodePudding user response：

You can't return two things at once, but there are couple of ways to output both objects on the console:

1. Assign each object to a variable, and output the variables one at a time
2. Store both objects together in a list, and output the list to the console

1. Assign each value to a different variable

The variables will be stored in the global environment, so they will be accessible subsequent to the execution of the if statement.

x <- -3
data <- data.frame(category = c("foo", "bar", "baz"))

if (x <= 0){
  my.text <- "Negative"
  my.values <- unique(data[["category"]])
}
 
## Now you can do as you please with these variables. For example:

cat("The value of x is", my.text)
#> The value of x is Negative

length(my.values)
#> [1] 3

^{Created on 2022-08-23 by the reprex package (v2.0.1)}

2. Immediately return a two-element list

x <- -3
data <- data.frame(category = c("foo", "bar", "baz"))


if (x <= 0){

  list(
    polarity = "Negative",
    values   = unique(data[["category"]])
  )

}
#> $polarity
#> [1] "Negative"
#> 
#> $values
#> [1] "foo" "bar" "baz"

^{Created on 2022-08-23 by the reprex package (v2.0.1)}

3. Bonus solution: Use cat() to print to the console

If you don't actually want to return the objects, but you just want to print them to the console, you can use cat(). Depending on your aims, you might also consider using message(), which is designed to give messages to the user (or a log).

x <- -3
data <- data.frame(category = c("foo", "bar", "baz"))


if (x <= 0){

  cat("Negative")
  cat(data[["category"]])
  
}
#> Negativefoo bar baz

### or consider:

if (x <= 0){
  
  message("Negative")
  message(data[["category"]])
  
}
#> Negative
#> foobarbaz

^{Created on 2022-08-23 by the reprex package (v2.0.1)}