R if-else

Used for conditional execution of code. A block of code is given and execueted to check if a given condition is true or flase. It goes for another block if the condition is false.

Syntax:
if (condition) {
# Code to be executed if the condition is TRUE
} else {
# Code to be executed if the condition is FALSE
}

num <- -5

if (num > 0) {
  print("The number is positive.")
} else {
  print("The number is non-positive (zero or negative).")
}

The above example checks the condition if num > 0 if the condition is false then it goes to the else block.

Comparison Operators

Multiple conditions are checked using else if.

Syntax:
if (condition1) {
# Code to be executed if the condition1 is TRUE
} else if (condition2) {
# Code to be executed if the condition1 is FALSE and condition2 is TRUE
} else {
# Code to be executed if the both the conditions are FALSE
}

check_sign <- function(num) {
  if (num > 0) {
    return("Positive")
  } else if (num < 0) {
    return("Negative")
  } else {
    return("Zero")
  }
}

result <- check_sign(7)
print(result)

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