Struct BigUint

pub struct BigUint(/* private fields */);

Methods from Deref<Target = BigUint>

pub const ZERO: BigUint

pub fn assign_from_slice(&mut self, slice: &[u32])

Assign a value to a BigUint.

The base 2³² digits are ordered least significant digit first.

pub fn to_bytes_be(&self) -> Vec<u8>

Returns the byte representation of the BigUint in big-endian byte order.

Examples

use num_bigint::BigUint;

let i = BigUint::parse_bytes(b"1125", 10).unwrap();
assert_eq!(i.to_bytes_be(), vec![4, 101]);

pub fn to_bytes_le(&self) -> Vec<u8>

Returns the byte representation of the BigUint in little-endian byte order.

Examples

use num_bigint::BigUint;

let i = BigUint::parse_bytes(b"1125", 10).unwrap();
assert_eq!(i.to_bytes_le(), vec![101, 4]);

pub fn to_u32_digits(&self) -> Vec<u32>

Returns the u32 digits representation of the BigUint ordered least significant digit first.

Examples

use num_bigint::BigUint;

assert_eq!(BigUint::from(1125u32).to_u32_digits(), vec![1125]);
assert_eq!(BigUint::from(4294967295u32).to_u32_digits(), vec![4294967295]);
assert_eq!(BigUint::from(4294967296u64).to_u32_digits(), vec![0, 1]);
assert_eq!(BigUint::from(112500000000u64).to_u32_digits(), vec![830850304, 26]);

pub fn to_u64_digits(&self) -> Vec<u64>

Returns the u64 digits representation of the BigUint ordered least significant digit first.

Examples

use num_bigint::BigUint;

assert_eq!(BigUint::from(1125u32).to_u64_digits(), vec![1125]);
assert_eq!(BigUint::from(4294967295u32).to_u64_digits(), vec![4294967295]);
assert_eq!(BigUint::from(4294967296u64).to_u64_digits(), vec![4294967296]);
assert_eq!(BigUint::from(112500000000u64).to_u64_digits(), vec![112500000000]);
assert_eq!(BigUint::from(1u128 << 64).to_u64_digits(), vec![0, 1]);

pub fn iter_u32_digits(&self) -> U32Digits<'_>

Returns an iterator of u32 digits representation of the BigUint ordered least significant digit first.

Examples

use num_bigint::BigUint;

assert_eq!(BigUint::from(1125u32).iter_u32_digits().collect::<Vec<u32>>(), vec![1125]);
assert_eq!(BigUint::from(4294967295u32).iter_u32_digits().collect::<Vec<u32>>(), vec![4294967295]);
assert_eq!(BigUint::from(4294967296u64).iter_u32_digits().collect::<Vec<u32>>(), vec![0, 1]);
assert_eq!(BigUint::from(112500000000u64).iter_u32_digits().collect::<Vec<u32>>(), vec![830850304, 26]);

pub fn iter_u64_digits(&self) -> U64Digits<'_>

Returns an iterator of u64 digits representation of the BigUint ordered least significant digit first.

Examples

use num_bigint::BigUint;

assert_eq!(BigUint::from(1125u32).iter_u64_digits().collect::<Vec<u64>>(), vec![1125]);
assert_eq!(BigUint::from(4294967295u32).iter_u64_digits().collect::<Vec<u64>>(), vec![4294967295]);
assert_eq!(BigUint::from(4294967296u64).iter_u64_digits().collect::<Vec<u64>>(), vec![4294967296]);
assert_eq!(BigUint::from(112500000000u64).iter_u64_digits().collect::<Vec<u64>>(), vec![112500000000]);
assert_eq!(BigUint::from(1u128 << 64).iter_u64_digits().collect::<Vec<u64>>(), vec![0, 1]);

pub fn to_str_radix(&self, radix: u32) -> String

Returns the integer formatted as a string in the given radix. radix must be in the range 2...36.

Examples

use num_bigint::BigUint;

let i = BigUint::parse_bytes(b"ff", 16).unwrap();
assert_eq!(i.to_str_radix(16), "ff");

pub fn to_radix_be(&self, radix: u32) -> Vec<u8>

Returns the integer in the requested base in big-endian digit order. The output is not given in a human readable alphabet but as a zero based u8 number. radix must be in the range 2...256.

Examples

use num_bigint::BigUint;

assert_eq!(BigUint::from(0xFFFFu64).to_radix_be(159),
           vec![2, 94, 27]);
// 0xFFFF = 65535 = 2*(159^2) + 94*159 + 27

pub fn to_radix_le(&self, radix: u32) -> Vec<u8>

Returns the integer in the requested base in little-endian digit order. The output is not given in a human readable alphabet but as a zero based u8 number. radix must be in the range 2...256.

Examples

use num_bigint::BigUint;

assert_eq!(BigUint::from(0xFFFFu64).to_radix_le(159),
           vec![27, 94, 2]);
// 0xFFFF = 65535 = 27 + 94*159 + 2*(159^2)

pub fn bits(&self) -> u64

Determines the fewest bits necessary to express the BigUint.

pub fn pow(&self, exponent: u32) -> BigUint

Returns self ^ exponent.

pub fn modpow(&self, exponent: &BigUint, modulus: &BigUint) -> BigUint

Returns (self ^ exponent) % modulus.

Panics if the modulus is zero.

pub fn modinv(&self, modulus: &BigUint) -> Option<BigUint>

Returns the modular multiplicative inverse if it exists, otherwise None.

This solves for x in the interval [0, modulus) such that self * x ≡ 1 (mod modulus). The solution exists if and only if gcd(self, modulus) == 1.

use num_bigint::BigUint;
use num_traits::{One, Zero};

let m = BigUint::from(383_u32);

// Trivial cases
assert_eq!(BigUint::zero().modinv(&m), None);
assert_eq!(BigUint::one().modinv(&m), Some(BigUint::one()));
let neg1 = &m - 1u32;
assert_eq!(neg1.modinv(&m), Some(neg1));

let a = BigUint::from(271_u32);
let x = a.modinv(&m).unwrap();
assert_eq!(x, BigUint::from(106_u32));
assert_eq!(x.modinv(&m).unwrap(), a);
assert!((a * x % m).is_one());

pub fn sqrt(&self) -> BigUint

Returns the truncated principal square root of self – see Roots::sqrt

pub fn cbrt(&self) -> BigUint

Returns the truncated principal cube root of self – see Roots::cbrt.

pub fn nth_root(&self, n: u32) -> BigUint

Returns the truncated principal nth root of self – see Roots::nth_root.

pub fn trailing_zeros(&self) -> Option<u64>

Returns the number of least-significant bits that are zero, or None if the entire number is zero.

pub fn trailing_ones(&self) -> u64

Returns the number of least-significant bits that are ones.

pub fn count_ones(&self) -> u64

Returns the number of one bits.

pub fn bit(&self, bit: u64) -> bool

Returns whether the bit in the given position is set

pub fn set_bit(&mut self, bit: u64, value: bool)

Sets or clears the bit in the given position

Note that setting a bit greater than the current bit length, a reallocation may be needed to store the new digits

Trait Implementations

impl Clone for BigUint

where BigUint: Clone,

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for BigUint

where BigUint: Debug,

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

Formats the value using the given formatter.

impl Deref for BigUint

type Target = BigUint

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl DerefMut for BigUint

fn deref_mut(&mut self) -> &mut Self::Target

Mutably dereferences the value.

impl Display for BigUint

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

Formats the value using the given formatter.

impl From<BigUint> for BigUint

fn from(inner: BigUint) -> Self

Converts to this type from the input type.

impl Hash for BigUint

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

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Ord for BigUint

fn cmp(&self, other: &BigUint) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for BigUint

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd for BigUint

fn partial_cmp(&self, other: &BigUint) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

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

Tests less than (for self and other) and is used by the < operator.

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

Tests less than or equal to (for self and other) and is used by the <= operator.

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

Tests greater than (for self and other) and is used by the > operator.

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

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl Eq for BigUint

impl StructuralPartialEq for BigUint