`sign`

returns a vector with the signs of the corresponding
elements of `x`

(the sign of a real number is 1, 0, or \(-1\)
if the number is positive, zero, or negative, respectively).

Note that `sign`

does not operate on complex vectors.

`sign(x)`

x

a numeric vector

This is an internal generic primitive function: methods
can be defined for it directly or via the
`Math`

group generic.

# NOT RUN { sign(pi) # == 1 sign(-2:3) # -1 -1 0 1 1 1 # }