malachite-float 0.9.1

The arbitrary-precision floating-point type Float, with efficient algorithms partially derived from MPFR.
Documentation 
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// Copyright © 2026 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 malachite_base::num::arithmetic::traits::Sign;
use malachite_base::num::basic::traits::NaN;
use malachite_base::num::conversion::traits::ExactFrom;
use malachite_base::test_util::generators::primitive_float_gen_var_11;
use malachite_float::Float;
use malachite_float::test_util::common::parse_hex_string;
use malachite_float::test_util::generators::{float_gen_var_2, float_gen_var_3, float_gen_var_14};
use malachite_q::Rational;
use std::cmp::Ordering::*;

#[test]
fn test_sign() {
    let test = |s, s_hex, out| {
        let x = parse_hex_string(s_hex);
        assert_eq!(x.to_string(), s);

        assert_eq!(x.sign(), out);
    };
    test("Infinity", "Infinity", Greater);
    test("-Infinity", "-Infinity", Less);
    test("0.0", "0x0.0", Greater);
    test("-0.0", "-0x0.0", Less);

    test("1.0", "0x1.0#1", Greater);
    test("2.0", "0x2.0#1", Greater);
    test("0.5", "0x0.8#1", Greater);
    test("0.33333333333333331", "0x0.55555555555554#53", Greater);
    test("1.4142135623730951", "0x1.6a09e667f3bcd#53", Greater);
    test("3.1415926535897931", "0x3.243f6a8885a30#53", Greater);
    test("too_big", "0x4.0E+268435455#1", Greater);
    test("too_small", "0x1.0E-268435456#1", Greater);

    test("-1.0", "-0x1.0#1", Less);
    test("-2.0", "-0x2.0#1", Less);
    test("-0.5", "-0x0.8#1", Less);
    test("-0.33333333333333331", "-0x0.55555555555554#53", Less);
    test("-1.4142135623730951", "-0x1.6a09e667f3bcd#53", Less);
    test("-3.1415926535897931", "-0x3.243f6a8885a30#53", Less);
    test("-too_big", "-0x4.0E+268435455#1", Less);
    test("-too_small", "-0x1.0E-268435456#1", Less);
}

#[test]
#[should_panic]
fn sign_fail() {
    Float::NAN.sign();
}

fn sign_properties_helper(x: Float) {
    let sign = x.sign();
    assert_ne!(sign, Equal);
    assert_eq!(if x.is_sign_positive() { Greater } else { Less }, sign);
    assert_eq!((-x).sign(), sign.reverse());
}

#[test]
fn sign_properties() {
    float_gen_var_2().test_properties(|x| {
        sign_properties_helper(x);
    });

    float_gen_var_14().test_properties(|x| {
        sign_properties_helper(x);
    });

    float_gen_var_3().test_properties(|x| {
        assert_eq!(x.sign(), Rational::exact_from(x).sign());
    });

    primitive_float_gen_var_11::<f64>().test_properties(|x| {
        assert_eq!(x.sign(), Float::from(x).sign());
    });
}