1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54
// Copyright © 2024 Mikhail Hogrefe
//
// This file is part of Malachite.
//
// Malachite is free software: you can redistribute it and/or modify it under the terms of the GNU
// Lesser General Public License (LGPL) as published by the Free Software Foundation; either version
// 3 of the License, or (at your option) any later version. See <https://www.gnu.org/licenses/>.
use crate::Float;
use crate::InnerFloat::{Finite, Infinity, Zero};
use core::cmp::Ordering::{self, *};
use malachite_base::num::arithmetic::traits::Sign;
impl Sign for Float {
/// Returns the sign of a [`Float`].
///
/// Returns `Greater` if the sign is positive and `Less` if the sign is negative. Never returns
/// `Equal`. Positive infinity and positive zero have a positive sign, and negative infinity and
/// negative zero have a negative sign.
///
/// # Worst-case complexity
/// Constant time and additional memory.
///
/// # Panics
/// Panics if `self` is NaN.
///
/// # Examples
/// ```
/// use malachite_base::num::arithmetic::traits::Sign;
/// use malachite_base::num::basic::traits::{
/// Infinity, NegativeInfinity, NegativeOne, NegativeZero, One, Zero,
/// };
/// use malachite_float::Float;
/// use std::cmp::Ordering::*;
///
/// assert_eq!(Float::INFINITY.sign(), Greater);
/// assert_eq!(Float::NEGATIVE_INFINITY.sign(), Less);
/// assert_eq!(Float::ZERO.sign(), Greater);
/// assert_eq!(Float::NEGATIVE_ZERO.sign(), Less);
/// assert_eq!(Float::ONE.sign(), Greater);
/// assert_eq!(Float::NEGATIVE_ONE.sign(), Less);
/// ```
fn sign(&self) -> Ordering {
if let Float(Infinity { sign } | Zero { sign } | Finite { sign, .. }) = self {
if *sign {
Greater
} else {
Less
}
} else {
panic!()
}
}
}