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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 crate::Float;
use malachite_base::num::arithmetic::traits::CanonicalUnitIPow;
impl CanonicalUnitIPow for Float {
/// Finds the power of $i$ that brings a [`Float`] into canonical unit form. The canonical unit
/// form of a [`Float`] is its absolute value, so this is 2 for values with the sign bit set,
/// negative zero and negative infinity included, since $x i^2 = -x$, and 0 otherwise, NaN
/// included.
///
/// # Worst-case complexity
/// Constant time and additional memory.
///
/// # Examples
/// ```
/// use malachite_base::num::arithmetic::traits::CanonicalUnitIPow;
/// use malachite_base::num::basic::traits::{NaN, NegativeZero};
/// use malachite_float::Float;
///
/// assert_eq!(Float::from(1.5).canonical_unit_i_pow(), 0);
/// assert_eq!(Float::from(-1.5).canonical_unit_i_pow(), 2);
/// assert_eq!(Float::NEGATIVE_ZERO.canonical_unit_i_pow(), 2);
/// assert_eq!(Float::NAN.canonical_unit_i_pow(), 0);
/// ```
#[inline]
fn canonical_unit_i_pow(&self) -> u64 {
if self.is_sign_negative() && !self.is_nan() {
2
} else {
0
}
}
}