malachite_nz/integer_polynomial/arithmetic/
neg.rs

1// Copyright © 2026 Mikhail Hogrefe
2//
3// This file is part of Malachite.
4//
5// Malachite is free software: you can redistribute it and/or modify it under the terms of the GNU
6// Lesser General Public License (LGPL) as published by the Free Software Foundation; either version
7// 3 of the License, or (at your option) any later version. See <https://www.gnu.org/licenses/>.
8
9use crate::integer_polynomial::IntegerPolynomial;
10use core::ops::Neg;
11use malachite_base::num::arithmetic::traits::NegAssign;
12
13impl Neg for IntegerPolynomial {
14    type Output = Self;
15
16    /// Negates an [`IntegerPolynomial`], taking it by value.
17    ///
18    /// $$
19    /// f(p) = -p.
20    /// $$
21    ///
22    /// # Worst-case complexity
23    /// $T(n) = O(n)$
24    ///
25    /// $M(n) = O(1)$
26    ///
27    /// where $T$ is time, $M$ is additional memory, and $n$ is `self.len()`.
28    ///
29    /// # Examples
30    /// ```
31    /// use core::str::FromStr;
32    /// use malachite_base::num::basic::traits::Zero;
33    /// use malachite_nz::integer_polynomial::IntegerPolynomial;
34    ///
35    /// let p = IntegerPolynomial::from_str("x^2-3*x+2").unwrap();
36    /// assert_eq!((-p).to_string(), "-x^2+3*x-2");
37    /// assert_eq!(-IntegerPolynomial::ZERO, IntegerPolynomial::ZERO);
38    /// ```
39    ///
40    /// This is equivalent to `fmpz_poly_neg` from `fmpz_poly/neg.c`, FLINT 3.6.0.
41    fn neg(mut self) -> Self {
42        self.neg_assign();
43        self
44    }
45}
46
47impl Neg for &IntegerPolynomial {
48    type Output = IntegerPolynomial;
49
50    /// Negates an [`IntegerPolynomial`], taking it by reference.
51    ///
52    /// $$
53    /// f(p) = -p.
54    /// $$
55    ///
56    /// # Worst-case complexity
57    /// $T(n) = O(n)$
58    ///
59    /// $M(n) = O(n)$
60    ///
61    /// where $T$ is time, $M$ is additional memory, and $n$ is the total number of bits of the
62    /// coefficients.
63    ///
64    /// # Examples
65    /// ```
66    /// use core::str::FromStr;
67    /// use malachite_base::num::basic::traits::Zero;
68    /// use malachite_nz::integer_polynomial::IntegerPolynomial;
69    ///
70    /// let p = IntegerPolynomial::from_str("x^2-3*x+2").unwrap();
71    /// assert_eq!((-&p).to_string(), "-x^2+3*x-2");
72    /// assert_eq!(-&IntegerPolynomial::ZERO, IntegerPolynomial::ZERO);
73    /// ```
74    ///
75    /// This is equivalent to `fmpz_poly_neg` from `fmpz_poly/neg.c`, FLINT 3.6.0.
76    fn neg(self) -> IntegerPolynomial {
77        IntegerPolynomial {
78            coefficients: self.coefficients.iter().map(|c| -c).collect(),
79        }
80    }
81}
82
83impl NegAssign for IntegerPolynomial {
84    /// Negates an [`IntegerPolynomial`] in place.
85    ///
86    /// $$
87    /// p \gets -p.
88    /// $$
89    ///
90    /// # Worst-case complexity
91    /// $T(n) = O(n)$
92    ///
93    /// $M(n) = O(1)$
94    ///
95    /// where $T$ is time, $M$ is additional memory, and $n$ is `self.len()`.
96    ///
97    /// # Examples
98    /// ```
99    /// use core::str::FromStr;
100    /// use malachite_base::num::arithmetic::traits::NegAssign;
101    /// use malachite_nz::integer_polynomial::IntegerPolynomial;
102    ///
103    /// let mut p = IntegerPolynomial::from_str("x^2-3*x+2").unwrap();
104    /// p.neg_assign();
105    /// assert_eq!(p.to_string(), "-x^2+3*x-2");
106    /// ```
107    fn neg_assign(&mut self) {
108        for c in &mut self.coefficients {
109            c.neg_assign();
110        }
111    }
112}
malachite_nz/integer_polynomial/arithmetic/neg.rs

malachite_nz/integer_polynomial/arithmetic/
neg.rs
