R retain the value of variable like SAS

In R, you can retain the value of a variable by assigning it to a new variable or by using the <<- operator.

Here's an example of how you can retain the value of a variable in R:

# Assign the value of a variable to a new variable
x <- 10
y <- x
x <- 20  # Change the value of x
print(y)  # The value of y remains 10

# Use the <<- operator to assign a value globally
z <- 5
foo <- function() {
  z <<- z + 1  # Increment the value of z globally
}
foo()
print(z)  # The value of z is now 6

In the first example, the value of y is assigned the value of x, so even if x changes, y retains its original value.

In the second example, the <<- operator is used inside a function to assign a new value to the global variable z. The value of z is incremented by 1 each time the foo function is called, and the updated value is retained globally