latitude <- sample(-90:90, 1)
# if is an expression: it gives the value of
# the branch that ran
location <- if (latitude == 0) {
"Equator"
} else if (latitude < 0) {
"Southern Hemisphere"
} else {
"Northern Hemisphere"
}
# On one line
sign <- if (latitude < 0) "-" else "+"
# Trap: no else and a false condition give NULL
no_else <- if (latitude > 90) "too far"
cat("latitude =", latitude, "\n")
cat("location =", location, "\n")
cat("sign =", sign, "\n")
cat("is.null(no_else) =", is.null(no_else), "\n")
# is.null(no_else) = TRUE