Function std::num::signum
pub fn signum<T: Signed>(value: T) -> T
Returns the sign of the number.
For float, f32, f64:
- 1.0 if the number is positive, +0.0 or INFINITY
- -1.0 if the number is negative, -0.0 or NEG_INFINITY
- NAN if the number is NAN
For int:
- 0 if the number is zero
- 1 if the number is positive
- -1 if the number is negative