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Modular

Struct Modular 

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pub struct Modular { /* private fields */ }
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An element of the ring ℤ/nℤ — an integer taken modulo a fixed modulus. This is the arbitrary-modulus generalisation of crate::Word8/…/crate::Word64 (whose modulus is a power of two): arithmetic WRAPS into [0, modulus), the cyclic group where overflow is the point, not a bug. The number-theory / crypto substrate — modular exponentiation and the extended-Euclid inverse live here, so RSA-style and finite-field code is exact.

INVARIANT: 0 ≤ value < modulus and modulus ≥ 1 (built via Modular::new, which reduces into range), so equal residues share one representation (Eq/Hash are structural). NOT ordered (ℤ/nℤ has no canonical total order).

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impl Modular

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pub fn new(value: BigInt, modulus: BigInt) -> Option<Modular>

Reduce value into the ring ℤ/modulusℤ. None for a non-positive modulus.

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pub fn from_i64(value: i64, modulus: i64) -> Option<Modular>

Convenience over machine integers (None if modulus ≤ 0).

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pub fn value(&self) -> &BigInt

The canonical representative in [0, modulus).

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pub fn modulus(&self) -> &BigInt

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pub fn is_zero(&self) -> bool

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pub fn add(&self, other: &Modular) -> Option<Modular>

self + otherNone when the moduli differ (a ring mismatch, like a Word width mismatch).

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pub fn sub(&self, other: &Modular) -> Option<Modular>

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pub fn mul(&self, other: &Modular) -> Option<Modular>

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pub fn negated(&self) -> Modular

The additive inverse −self (i.e. modulus − value, reduced).

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pub fn pow(&self, exp: u64) -> Modular

self^exp by fast modular exponentiation (square-and-multiply). 0^0 == 1.

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pub fn inverse(&self) -> Option<Modular>

The multiplicative inverse self⁻¹ (extended Euclid). None unless gcd(value, modulus) == 1 (the value must be a unit of the ring).

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pub fn div(&self, other: &Modular) -> Option<Modular>

self / other = self · other⁻¹None on a modulus mismatch or a non-invertible divisor.

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impl Clone for Modular

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fn clone(&self) -> Modular

Returns a duplicate of the value. Read more
1.0.0 (const: unstable) · Source§

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source. Read more
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impl Debug for Modular

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fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter. Read more
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impl Display for Modular

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fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter. Read more
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impl Eq for Modular

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impl Hash for Modular

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fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher. Read more
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fn hash_slice<H>(data: &[Self], state: &mut H)
where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher. Read more
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impl PartialEq for Modular

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fn eq(&self, other: &Modular) -> bool

Equality operator ==. Read more
1.0.0 (const: unstable) · Source§

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=. Read more
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impl StructuralPartialEq for Modular

Auto Trait Implementations§

Blanket Implementations§

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impl<T> Any for T
where T: 'static + ?Sized,

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fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more
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impl<T> Borrow<T> for T
where T: ?Sized,

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fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
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impl<T> BorrowMut<T> for T
where T: ?Sized,

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fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more
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impl<T> CloneToUninit for T
where T: Clone,

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unsafe fn clone_to_uninit(&self, dest: *mut u8)

🔬This is a nightly-only experimental API. (clone_to_uninit)
Performs copy-assignment from self to dest. Read more
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impl<T> From<T> for T

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fn from(t: T) -> T

Returns the argument unchanged.

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impl<T, U> Into<U> for T
where U: From<T>,

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fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

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impl<T> ToOwned for T
where T: Clone,

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type Owned = T

The resulting type after obtaining ownership.
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fn to_owned(&self) -> T

Creates owned data from borrowed data, usually by cloning. Read more
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fn clone_into(&self, target: &mut T)

Uses borrowed data to replace owned data, usually by cloning. Read more
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impl<T> ToString for T
where T: Display + ?Sized,

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fn to_string(&self) -> String

Converts the given value to a String. Read more
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impl<T, U> TryFrom<U> for T
where U: Into<T>,

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type Error = Infallible

The type returned in the event of a conversion error.
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fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

Performs the conversion.
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impl<T, U> TryInto<U> for T
where U: TryFrom<T>,

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type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.
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fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.