Struct malachite_float::ComparableFloat
source · pub struct ComparableFloat(pub Float);Expand description
ComparableFloat is a wrapper around a Float, taking the Float by value.
CompatableFloat has different comparison behavior than Float. See the Float
documentation for its comparison behavior, which is largely derived from the IEEE 754
specification; the ComparableFloat behavior, on the other hand, is more mathematically
well-behaved, and respects the principle that equality should be the finest equivalence
relation: that is, that two equal objects should not be different in any way.
To be more specific: when a Float is wrapped in a ComparableFloat,
NaNis not equal to any otherFloat, but equal to itself;- Positive and negative zero are not equal to each other;
- Ordering is total. Negative zero is ordered to be smaller than positive zero, and
NaNis arbitrarily ordered to be between the two zeros; - Two
Floats with different precisions but representing the same value are unequal, and the one with the greater precision is ordered to be larger; - The hashing function is compatible with equality.
The analogous wrapper for primitive floats is
NiceFloat. However,
NiceFloat also facilitates better string
conversion, something that isn’t necessary for Floats
ComparableFloat owns its float. This is useful in many cases, for example if you want to use
Floats as keys in a hash map. In other situations, it is better to use
ComparableFloatRef, which only has a reference to its float.
Tuple Fields§
§0: FloatImplementations§
source§impl ComparableFloat
impl ComparableFloat
pub const fn as_ref(&self) -> ComparableFloatRef<'_>
Methods from Deref<Target = Float>§
sourcepub fn abs_negative_zero_ref(&self) -> Float
pub fn abs_negative_zero_ref(&self) -> Float
If self is negative zero, returns positive zero; otherwise, returns self, taking self
by reference.
Worst-case complexity
$T(n) = O(n)$
$M(n) = O(n)$
where $T$ is time, $M$ is additional memory, and $n$ is self.significant_bits().
Examples
use malachite_base::num::basic::traits::{
Infinity, NaN, NegativeInfinity, NegativeOne, NegativeZero, One, Zero
};
use malachite_float::{ComparableFloat, Float};
assert_eq!(
ComparableFloat(Float::NAN.abs_negative_zero_ref()),
ComparableFloat(Float::NAN)
);
assert_eq!(Float::INFINITY.abs_negative_zero_ref(), Float::INFINITY);
assert_eq!(Float::NEGATIVE_INFINITY.abs_negative_zero_ref(), Float::NEGATIVE_INFINITY);
assert_eq!(
ComparableFloat(Float::ZERO.abs_negative_zero_ref()),
ComparableFloat(Float::ZERO)
);
assert_eq!(
ComparableFloat(Float::NEGATIVE_ZERO.abs_negative_zero_ref()),
ComparableFloat(Float::ZERO)
);
assert_eq!(Float::ONE.abs_negative_zero_ref(), Float::ONE);
assert_eq!(Float::NEGATIVE_ONE.abs_negative_zero_ref(), Float::NEGATIVE_ONE);sourcepub fn is_nan(&self) -> bool
pub fn is_nan(&self) -> bool
Determines whether a Float is NaN.
Worst-case complexity
Constant time and additional memory.
Examples
use malachite_base::num::basic::traits::{NaN, One};
use malachite_float::Float;
assert_eq!(Float::NAN.is_nan(), true);
assert_eq!(Float::ONE.is_nan(), false);sourcepub fn is_finite(&self) -> bool
pub fn is_finite(&self) -> bool
Determines whether a Float is finite.
NaN is not finite.
Worst-case complexity
Constant time and additional memory.
Examples
use malachite_base::num::basic::traits::{Infinity, NaN, One};
use malachite_float::Float;
assert_eq!(Float::NAN.is_finite(), false);
assert_eq!(Float::INFINITY.is_finite(), false);
assert_eq!(Float::ONE.is_finite(), true);sourcepub fn is_infinite(&self) -> bool
pub fn is_infinite(&self) -> bool
Determines whether a Float is infinite.
NaN is not infinite.
Worst-case complexity
Constant time and additional memory.
Examples
use malachite_base::num::basic::traits::{Infinity, NaN, One};
use malachite_float::Float;
assert_eq!(Float::NAN.is_infinite(), false);
assert_eq!(Float::INFINITY.is_infinite(), true);
assert_eq!(Float::ONE.is_infinite(), false);sourcepub fn is_positive_zero(&self) -> bool
pub fn is_positive_zero(&self) -> bool
Determines whether a Float is positive zero.
Worst-case complexity
Constant time and additional memory.
Examples
use malachite_base::num::basic::traits::{Infinity, NaN, NegativeZero, One, Zero};
use malachite_float::Float;
assert_eq!(Float::NAN.is_positive_zero(), false);
assert_eq!(Float::INFINITY.is_positive_zero(), false);
assert_eq!(Float::ONE.is_positive_zero(), false);
assert_eq!(Float::ZERO.is_positive_zero(), true);
assert_eq!(Float::NEGATIVE_ZERO.is_positive_zero(), false);sourcepub fn is_negative_zero(&self) -> bool
pub fn is_negative_zero(&self) -> bool
Determines whether a Float is negative zero.
Worst-case complexity
Constant time and additional memory.
Examples
use malachite_base::num::basic::traits::{Infinity, NaN, NegativeZero, One, Zero};
use malachite_float::Float;
assert_eq!(Float::NAN.is_negative_zero(), false);
assert_eq!(Float::INFINITY.is_negative_zero(), false);
assert_eq!(Float::ONE.is_negative_zero(), false);
assert_eq!(Float::ZERO.is_negative_zero(), false);
assert_eq!(Float::NEGATIVE_ZERO.is_negative_zero(), true);sourcepub fn is_zero(&self) -> bool
pub fn is_zero(&self) -> bool
Determines whether a Float is zero (positive or negative).
Worst-case complexity
Constant time and additional memory.
Examples
use malachite_base::num::basic::traits::{Infinity, NaN, NegativeZero, One, Zero};
use malachite_float::Float;
assert_eq!(Float::NAN.is_zero(), false);
assert_eq!(Float::INFINITY.is_zero(), false);
assert_eq!(Float::ONE.is_zero(), false);
assert_eq!(Float::ZERO.is_zero(), true);
assert_eq!(Float::NEGATIVE_ZERO.is_zero(), true);sourcepub fn is_normal(&self) -> bool
pub fn is_normal(&self) -> bool
Determines whether a Float is normal, that is, finite and nonzero.
There is no notion of subnormal Floats.
Worst-case complexity
Constant time and additional memory.
Examples
use malachite_base::num::basic::traits::{Infinity, NaN, NegativeZero, One, Zero};
use malachite_float::Float;
assert_eq!(Float::NAN.is_normal(), false);
assert_eq!(Float::INFINITY.is_normal(), false);
assert_eq!(Float::ZERO.is_normal(), false);
assert_eq!(Float::NEGATIVE_ZERO.is_normal(), false);
assert_eq!(Float::ONE.is_normal(), true);sourcepub fn is_sign_positive(&self) -> bool
pub fn is_sign_positive(&self) -> bool
Determines whether a Float’s sign is positive.
A NaN has no sign, so this function returns false when given a NaN.
Worst-case complexity
Constant time and additional memory.
Examples
use malachite_base::num::basic::traits::{
Infinity, NaN, NegativeInfinity, NegativeOne, NegativeZero, One, Zero
};
use malachite_float::Float;
assert_eq!(Float::NAN.is_sign_positive(), false);
assert_eq!(Float::INFINITY.is_sign_positive(), true);
assert_eq!(Float::NEGATIVE_INFINITY.is_sign_positive(), false);
assert_eq!(Float::ZERO.is_sign_positive(), true);
assert_eq!(Float::NEGATIVE_ZERO.is_sign_positive(), false);
assert_eq!(Float::ONE.is_sign_positive(), true);
assert_eq!(Float::NEGATIVE_ONE.is_sign_positive(), false);sourcepub fn is_sign_negative(&self) -> bool
pub fn is_sign_negative(&self) -> bool
Determines whether a Float’s sign is negative.
A NaN has no sign, so this function returns false when given a NaN.
Worst-case complexity
Constant time and additional memory.
Examples
use malachite_base::num::basic::traits::{
Infinity, NaN, NegativeInfinity, NegativeOne, NegativeZero, One, Zero
};
use malachite_float::Float;
assert_eq!(Float::NAN.is_sign_negative(), false);
assert_eq!(Float::INFINITY.is_sign_negative(), false);
assert_eq!(Float::NEGATIVE_INFINITY.is_sign_negative(), true);
assert_eq!(Float::ZERO.is_sign_negative(), false);
assert_eq!(Float::NEGATIVE_ZERO.is_sign_negative(), true);
assert_eq!(Float::ONE.is_sign_negative(), false);
assert_eq!(Float::NEGATIVE_ONE.is_sign_negative(), true);sourcepub fn classify(&self) -> FpCategory
pub fn classify(&self) -> FpCategory
Classifies a Float into one of several categories.
Worst-case complexity
Constant time and additional memory.
Examples
use malachite_base::num::basic::traits::{
Infinity, NaN, NegativeInfinity, NegativeOne, NegativeZero, One, Zero
};
use malachite_float::Float;
use std::num::FpCategory;
assert_eq!(Float::NAN.classify(), FpCategory::Nan);
assert_eq!(Float::INFINITY.classify(), FpCategory::Infinite);
assert_eq!(Float::NEGATIVE_INFINITY.classify(), FpCategory::Infinite);
assert_eq!(Float::ZERO.classify(), FpCategory::Zero);
assert_eq!(Float::NEGATIVE_ZERO.classify(), FpCategory::Zero);
assert_eq!(Float::ONE.classify(), FpCategory::Normal);
assert_eq!(Float::NEGATIVE_ONE.classify(), FpCategory::Normal);sourcepub fn to_non_nan(&self) -> Option<Float>
pub fn to_non_nan(&self) -> Option<Float>
Turns a NaN into a None and wraps any non-NaN Float with a Some. The Float is
taken by reference.
Worst-case complexity
$T(n) = O(n)$
$M(n) = O(n)$
where $T$ is time, $M$ is additional memory, and $n$ is self.significant_bits().
Examples
use malachite_base::num::basic::traits::{Infinity, NaN, NegativeZero, One, Zero};
use malachite_float::Float;
assert_eq!(Float::NAN.to_non_nan(), None);
assert_eq!(Float::INFINITY.to_non_nan(), Some(Float::INFINITY));
assert_eq!(Float::ZERO.to_non_nan(), Some(Float::ZERO));
assert_eq!(Float::NEGATIVE_ZERO.to_non_nan(), Some(Float::NEGATIVE_ZERO));
assert_eq!(Float::ONE.to_non_nan(), Some(Float::ONE));sourcepub fn to_finite(&self) -> Option<Float>
pub fn to_finite(&self) -> Option<Float>
Turns any Float that’s NaN or infinite into a None and wraps any finite Float
with a Some. The Float is taken by reference.
Worst-case complexity
$T(n) = O(n)$
$M(n) = O(n)$
where $T$ is time, $M$ is additional memory, and $n$ is self.significant_bits().
Examples
use malachite_base::num::basic::traits::{Infinity, NaN, NegativeZero, One, Zero};
use malachite_float::Float;
assert_eq!(Float::NAN.to_finite(), None);
assert_eq!(Float::INFINITY.to_finite(), None);
assert_eq!(Float::ZERO.to_finite(), Some(Float::ZERO));
assert_eq!(Float::NEGATIVE_ZERO.to_finite(), Some(Float::NEGATIVE_ZERO));
assert_eq!(Float::ONE.to_finite(), Some(Float::ONE));sourcepub fn complexity(&self) -> u64
pub fn complexity(&self) -> u64
Determines a Float’s complexity. The complexity is defined as follows:
$$ f(\text{NaN}) = f(\pm\infty) = f(\pm 0.0) = 1, $$
and, if $x$ is finite and nonzero,
$$ f(x) = \max(|\lfloor \log_2 x\rfloor|, p), $$
where $p$ is the precision of $x$.
Informally, the complexity is proportional to the number of characters you would need to
write the Float out without using exponents.
See also the Float implementation of SignificantBits.
Worst-case complexity
Constant time and additional memory.
Examples
use malachite_base::num::arithmetic::traits::PowerOf2;
use malachite_base::num::basic::traits::{NaN, One};
use malachite_float::Float;
assert_eq!(Float::NAN.complexity(), 1);
assert_eq!(Float::ONE.complexity(), 1);
assert_eq!(Float::one_prec(100).complexity(), 100);
assert_eq!(Float::from(std::f64::consts::PI).complexity(), 53);
assert_eq!(Float::power_of_2(100u64).complexity(), 100);
assert_eq!(Float::power_of_2(-100i64).complexity(), 100);sourcepub fn to_significand(&self) -> Option<Natural>
pub fn to_significand(&self) -> Option<Natural>
Gets the significand of a Float, taking the Float by value.
The significand is the smallest positive integer which is some power of 2 times the
Float, and whose number of significant bits is a multiple of the limb width. If the
Float is NaN, infinite, or zero, then None is returned.
Worst-case complexity
Constant time and additional memory.
Examples
use malachite_base::num::arithmetic::traits::PowerOf2;
use malachite_base::num::basic::traits::{Infinity, NaN, One, Zero};
use malachite_nz::natural::Natural;
use malachite_float::Float;
assert_eq!(Float::NAN.to_significand(), None);
assert_eq!(Float::INFINITY.to_significand(), None);
assert_eq!(Float::ZERO.to_significand(), None);
assert_eq!(Float::ONE.to_significand(), Some(Natural::power_of_2(63)));
assert_eq!(
Float::from(std::f64::consts::PI).to_significand().unwrap(),
14488038916154245120u64
);sourcepub fn significand_ref(&self) -> Option<&Natural>
pub fn significand_ref(&self) -> Option<&Natural>
Returns a reference to the significand of a Float.
The significand is the smallest positive integer which is some power of 2 times the
Float, and whose number of significant bits is a multiple of the limb width. If the
Float is NaN, infinite, or zero, then None is returned.
Worst-case complexity
Constant time and additional memory.
Examples
use malachite_base::num::arithmetic::traits::PowerOf2;
use malachite_base::num::basic::traits::{Infinity, NaN, One, Zero};
use malachite_nz::natural::Natural;
use malachite_float::Float;
assert_eq!(Float::NAN.significand_ref(), None);
assert_eq!(Float::INFINITY.significand_ref(), None);
assert_eq!(Float::ZERO.significand_ref(), None);
assert_eq!(*Float::ONE.significand_ref().unwrap(), Natural::power_of_2(63));
assert_eq!(
*Float::from(std::f64::consts::PI).significand_ref().unwrap(),
14488038916154245120u64
);sourcepub fn get_exponent(&self) -> Option<i64>
pub fn get_exponent(&self) -> Option<i64>
Returns a Float’s exponent.
$$ f(\text{NaN}) = f(\pm\infty) = f(\pm 0.0) = \text{None}, $$
and, if $x$ is finite and nonzero,
$$ f(x) = \operatorname{Some}(\lfloor \log_2 x \rfloor + 1). $$
Worst-case complexity
Constant time and additional memory.
Examples
use malachite_base::num::arithmetic::traits::PowerOf2;
use malachite_base::num::basic::traits::{Infinity, NaN, One, Zero};
use malachite_nz::natural::Natural;
use malachite_float::Float;
assert_eq!(Float::NAN.get_exponent(), None);
assert_eq!(Float::INFINITY.get_exponent(), None);
assert_eq!(Float::ZERO.get_exponent(), None);
assert_eq!(Float::ONE.get_exponent(), Some(1));
assert_eq!(Float::from(std::f64::consts::PI).get_exponent(), Some(2));
assert_eq!(Float::power_of_2(100u64).get_exponent(), Some(101));
assert_eq!(Float::power_of_2(-100i64).get_exponent(), Some(-99));sourcepub fn get_prec(&self) -> Option<u64>
pub fn get_prec(&self) -> Option<u64>
Returns a Float’s precision. The precision is a positive integer denoting how many of
the Float’s bits are significant.
Only Floats that are finite and nonzero have a precision. For other Floats, None
is returned.
Worst-case complexity
Constant time and additional memory.
Examples
use malachite_base::num::basic::traits::{Infinity, NaN, One, Zero};
use malachite_nz::natural::Natural;
use malachite_float::Float;
assert_eq!(Float::NAN.get_prec(), None);
assert_eq!(Float::INFINITY.get_prec(), None);
assert_eq!(Float::ZERO.get_prec(), None);
assert_eq!(Float::ONE.get_prec(), Some(1));
assert_eq!(Float::one_prec(100).get_prec(), Some(100));
assert_eq!(Float::from(std::f64::consts::PI).get_prec(), Some(53));sourcepub fn ulp(&self) -> Option<Float>
pub fn ulp(&self) -> Option<Float>
Gets a Float’s ulp (unit in last place, or unit of least precision).
If the Float is positive, its ulp is the distance to the next-largest Float with
the same precision; if it is negative, the next-smallest. (This definition works even if
the Float is the largest in its binade.)
If the Float is NaN, infinite, or zero, then None is returned.
$$ f(\text{NaN}) = f(\pm\infty) = f(\pm 0.0) = \text{None}, $$
and, if $x$ is finite and nonzero,
$$ f(x) = \operatorname{Some}(2^{\lfloor \log_2 x \rfloor-p+1}), $$ where $p$ is the precision of $x$.
Worst-case complexity
$T(n) = O(n)$
$M(n) = O(n)$
where $T$ is time, $M$ is additional memory, and $n$ is self.significant_bits().
Examples
use malachite_base::num::arithmetic::traits::PowerOf2;
use malachite_base::num::basic::traits::{Infinity, NaN, NegativeOne, One, Zero};
use malachite_nz::natural::Natural;
use malachite_float::Float;
assert_eq!(Float::NAN.ulp(), None);
assert_eq!(Float::INFINITY.ulp(), None);
assert_eq!(Float::ZERO.ulp(), None);
let s = Float::ONE.ulp().map(|x| x.to_string());
assert_eq!(s.as_ref().map(|s| s.as_str()), Some("1.0"));
let s = Float::one_prec(100).ulp().map(|x| x.to_string());
assert_eq!(s.as_ref().map(|s| s.as_str()), Some("2.0e-30"));
let s = Float::from(std::f64::consts::PI).ulp().map(|x| x.to_string());
assert_eq!(s.as_ref().map(|s| s.as_str()), Some("4.0e-16"));
let s = Float::power_of_2(100u64).ulp().map(|x| x.to_string());
assert_eq!(s.as_ref().map(|s| s.as_str()), Some("1.0e30"));
let s = Float::power_of_2(-100i64).ulp().map(|x| x.to_string());
assert_eq!(s.as_ref().map(|s| s.as_str()), Some("8.0e-31"));
let s = Float::NEGATIVE_ONE.ulp().map(|x| x.to_string());
assert_eq!(s.as_ref().map(|s| s.as_str()), Some("1.0"));sourcepub fn sci_mantissa_and_exponent_round<T: PrimitiveFloat>(
&self,
rm: RoundingMode
) -> Option<(T, i64, Ordering)>
pub fn sci_mantissa_and_exponent_round<T: PrimitiveFloat>( &self, rm: RoundingMode ) -> Option<(T, i64, Ordering)>
Returns a Float’s scientific mantissa and exponent, rounding according to the specified
rounding mode. An Ordering is also returned, indicating whether the mantissa and
exponent represent a value that is less than, equal to, or greater than the original value.
When $x$ is positive, we can write $x = 2^{e_s}m_s$, where $e_s$ is an integer and $m_s$ is
a rational number with $1 \leq m_s < 2$. We represent the rational mantissa as a float. The
conversion might not be exact, so we round to the nearest float using the provided rounding
mode. If the rounding mode is Exact but the conversion is not exact, None is returned.
$$
f(x, r) \approx \left (\frac{x}{2^{\lfloor \log_2 x \rfloor}},
\lfloor \log_2 x \rfloor\right ).
$$
Worst-case complexity
$T(n) = O(n)$
$M(n) = O(1)$
where $T$ is time, $M$ is additional memory, and $n$ is self.significant_bits().
Examples
use malachite_base::num::arithmetic::traits::Pow;
use malachite_base::num::conversion::traits::SciMantissaAndExponent;
use malachite_base::num::float::NiceFloat;
use malachite_base::rounding_modes::RoundingMode;
use malachite_float::Float;
use malachite_nz::natural::Natural;
use std::cmp::Ordering;
let test = |x: Float, rm: RoundingMode, out: Option<(f32, i64, Ordering)>| {
assert_eq!(
x.sci_mantissa_and_exponent_round(rm)
.map(|(m, e, o)| (NiceFloat(m), e, o)),
out.map(|(m, e, o)| (NiceFloat(m), e, o))
);
};
test(Float::from(3u32), RoundingMode::Floor, Some((1.5, 1, Ordering::Equal)));
test(Float::from(3u32), RoundingMode::Down, Some((1.5, 1, Ordering::Equal)));
test(Float::from(3u32), RoundingMode::Ceiling, Some((1.5, 1, Ordering::Equal)));
test(Float::from(3u32), RoundingMode::Up, Some((1.5, 1, Ordering::Equal)));
test(Float::from(3u32), RoundingMode::Nearest, Some((1.5, 1, Ordering::Equal)));
test(Float::from(3u32), RoundingMode::Exact, Some((1.5, 1, Ordering::Equal)));
let x = Float::from(std::f64::consts::PI);
test(x.clone(), RoundingMode::Floor, Some((1.5707963, 1, Ordering::Less)));
test(x.clone(), RoundingMode::Down, Some((1.5707963, 1, Ordering::Less)));
test(x.clone(), RoundingMode::Ceiling, Some((1.5707964, 1, Ordering::Greater)));
test(x.clone(), RoundingMode::Up, Some((1.5707964, 1, Ordering::Greater)));
test(x.clone(), RoundingMode::Nearest, Some((1.5707964, 1, Ordering::Greater)));
test(x.clone(), RoundingMode::Exact, None);
test(
Float::from(1000000000u32),
RoundingMode::Nearest,
Some((1.8626451, 29, Ordering::Equal)),
);
test(
Float::from(Natural::from(10u32).pow(52)),
RoundingMode::Nearest,
Some((1.670478, 172, Ordering::Greater)),
);
test(Float::from(Natural::from(10u32).pow(52)), RoundingMode::Exact, None);Trait Implementations§
source§impl Clone for ComparableFloat
impl Clone for ComparableFloat
source§fn clone(&self) -> ComparableFloat
fn clone(&self) -> ComparableFloat
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source. Read moresource§impl Debug for ComparableFloat
impl Debug for ComparableFloat
source§impl Deref for ComparableFloat
impl Deref for ComparableFloat
source§impl Display for ComparableFloat
impl Display for ComparableFloat
source§impl Hash for ComparableFloat
impl Hash for ComparableFloat
source§fn hash<H: Hasher>(&self, state: &mut H)
fn hash<H: Hasher>(&self, state: &mut H)
Computes a hash of a ComparableFloat.
The hash is compatible with ComparableFloat equality: all NaNs hash to the same value.
Worst-case complexity
$T(n) = O(n)$
$M(n) = O(1)$
where $T$ is time, $M$ is additional memory, and $n$ is self.significant_bits().
source§impl LowerHex for ComparableFloat
impl LowerHex for ComparableFloat
source§impl Ord for ComparableFloat
impl Ord for ComparableFloat
source§fn cmp(&self, other: &ComparableFloat) -> Ordering
fn cmp(&self, other: &ComparableFloat) -> Ordering
Compares two ComparableFloats.
This implementation does not follow the IEEE 754 standard. This is how
ComparableFloats are ordered, least to greatest:
- Negative infinity
- Negative nonzero finite floats
- Negative zero
- NaN
- Positive zero
- Positive nonzero finite floats
- Positive infinity
For different comparison behavior that follows the IEEE 754 standard, consider just using
Float.
Worst-case complexity
$T(n) = O(n)$
$M(n) = O(1)$
where $T$ is time, $M$ is additional memory, and $n$ is
max(self.significant_bits(), other.significant_bits()).
Examples
use malachite_base::num::basic::traits::{
Infinity, NaN, NegativeInfinity, NegativeOne, NegativeZero, One, OneHalf, Zero
};
use malachite_float::{ComparableFloat, Float};
use std::cmp::Ordering;
use std::str::FromStr;
assert_eq!(
ComparableFloat(Float::NAN).partial_cmp(&ComparableFloat(Float::NAN)),
Some(Ordering::Equal)
);
assert!(ComparableFloat(Float::ZERO) > ComparableFloat(Float::NEGATIVE_ZERO));
assert!(ComparableFloat(Float::ONE) < ComparableFloat(Float::one_prec(100)));
assert!(ComparableFloat(Float::INFINITY) > ComparableFloat(Float::ONE));
assert!(ComparableFloat(Float::NEGATIVE_INFINITY) < ComparableFloat(Float::ONE));
assert!(ComparableFloat(Float::ONE_HALF) < ComparableFloat(Float::ONE));
assert!(ComparableFloat(Float::ONE_HALF) > ComparableFloat(Float::NEGATIVE_ONE));1.21.0 · source§fn max(self, other: Self) -> Selfwhere
Self: Sized,
fn max(self, other: Self) -> Selfwhere
Self: Sized,
source§impl OrdAbs for ComparableFloat
impl OrdAbs for ComparableFloat
source§fn cmp_abs(&self, other: &ComparableFloat) -> Ordering
fn cmp_abs(&self, other: &ComparableFloat) -> Ordering
Compares the absolute values of two ComparableFloats.
This implementation does not follow the IEEE 754 standard. This is how
ComparableFloats are ordered by absolute value, from least to greatest:
- NaN
- Positive and negative zero
- Nonzero finite floats
- Positive and negative infinity
For different comparison behavior that follows the IEEE 754 standard, consider just using
Float.
Worst-case complexity
$T(n) = O(n)$
$M(n) = O(1)$
where $T$ is time, $M$ is additional memory, and $n$ is
max(self.significant_bits(), other.significant_bits()).
Examples
use malachite_base::num::basic::traits::{
Infinity, NaN, NegativeInfinity, NegativeOne, NegativeZero, One, OneHalf, Zero
};
use malachite_base::num::comparison::traits::PartialOrdAbs;
use malachite_float::{ComparableFloat, Float};
use std::cmp::Ordering;
use std::str::FromStr;
assert_eq!(
ComparableFloat(Float::NAN).partial_cmp_abs(&ComparableFloat(Float::NAN)),
Some(Ordering::Equal)
);
assert_eq!(
ComparableFloat(Float::ZERO).partial_cmp_abs(&ComparableFloat(Float::NEGATIVE_ZERO)),
Some(Ordering::Equal)
);
assert!(ComparableFloat(Float::ONE).lt_abs(&ComparableFloat(Float::one_prec(100))));
assert!(ComparableFloat(Float::INFINITY).gt_abs(&ComparableFloat(Float::ONE)));
assert!(ComparableFloat(Float::NEGATIVE_INFINITY).gt_abs(&ComparableFloat(Float::ONE)));
assert!(ComparableFloat(Float::ONE_HALF).lt_abs(&ComparableFloat(Float::ONE)));
assert!(ComparableFloat(Float::ONE_HALF).lt_abs(&ComparableFloat(Float::NEGATIVE_ONE)));source§impl PartialEq for ComparableFloat
impl PartialEq for ComparableFloat
source§fn eq(&self, other: &ComparableFloat) -> bool
fn eq(&self, other: &ComparableFloat) -> bool
Compares two ComparableFloats for equality.
This implementation ignores the IEEE 754 standard in favor of an equality operation that
respects the expected properties of symmetry, reflexivity, and transitivity. Using
ComparableFloat, NaNs are equal to themselves. There is a single, unique NaN;
there’s no concept of signalling NaNs. Positive and negative zero are two distinct
values, not equal to each other. ComparableFloats with different precisions are
unequal.
Worst-case complexity
$T(n) = O(n)$
$M(n) = O(1)$
where $T$ is time, $M$ is additional memory, and $n$ is
max(self.significant_bits(), other.significant_bits()).
Examples
use malachite_base::num::basic::traits::{NaN, NegativeZero, One, Two, Zero};
use malachite_float::{ComparableFloat, Float};
assert_eq!(ComparableFloat(Float::NAN), ComparableFloat(Float::NAN));
assert_eq!(ComparableFloat(Float::ZERO), ComparableFloat(Float::ZERO));
assert_eq!(ComparableFloat(Float::NEGATIVE_ZERO), ComparableFloat(Float::NEGATIVE_ZERO));
assert_ne!(ComparableFloat(Float::ZERO), ComparableFloat(Float::NEGATIVE_ZERO));
assert_eq!(ComparableFloat(Float::ONE), ComparableFloat(Float::ONE));
assert_ne!(ComparableFloat(Float::ONE), ComparableFloat(Float::TWO));
assert_ne!(ComparableFloat(Float::ONE), ComparableFloat(Float::one_prec(100)));source§impl PartialOrd for ComparableFloat
impl PartialOrd for ComparableFloat
source§fn partial_cmp(&self, other: &ComparableFloat) -> Option<Ordering>
fn partial_cmp(&self, other: &ComparableFloat) -> Option<Ordering>
Compares two ComparableFloats.
See the documentation for the Ord implementation.
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self and other) and is used by the <=
operator. Read moresource§impl PartialOrdAbs for ComparableFloat
impl PartialOrdAbs for ComparableFloat
source§fn partial_cmp_abs(&self, other: &ComparableFloat) -> Option<Ordering>
fn partial_cmp_abs(&self, other: &ComparableFloat) -> Option<Ordering>
Compares the absolute values of two ComparableFloatRefs.
See the documentation for the Ord implementation.