Class: Integer (Ruby 2.7.3)
Description: Class : Integer - Ruby 2.7.3

### Home Classes Methods

### In Files

- prime.rb

### Parent

Object

### Methods

- ::each_prime
- ::from_prime_division
- #prime?
- #prime_division

### Class/Module Index

Quicksearch

- Integer
- Prime
- Prime::EratosthenesGenerator
- Prime::EratosthenesSieve
- Prime::Generator23
- Prime::PseudoPrimeGenerator
- Prime::TrialDivision
- Prime::TrialDivisionGenerator

No matching classes.

# Integer

### Public Class Methods

each_prime(ubound) click to toggle source

Iterates the given block over all prime numbers.

See `Prime`#each for more details.

                   # File prime.rb, line 49
    def Integer.each_prime(ubound, &block) # :yields: prime
      Prime.each(ubound, &block)
    end

from_prime_division(pd) click to toggle source

Re-composes a prime factorization and returns the product.

See `Prime#int_from_prime_division` for more details.

                   # File prime.rb, line 22
    def Integer.from_prime_division(pd)
      Prime.int_from_prime_division(pd)
    end

### Public Instance Methods

prime?() click to toggle source

Returns true if `self` is a prime number, else returns false.

                   # File prime.rb, line 34
    def prime?
      return self >= 2 if self <= 3
      return true if self == 5
      return false unless 30.gcd(self) == 1
      (7..Integer.sqrt(self)).step(30) do |p|
        return false if
          self%(p)    == 0 || self%(p+4)  == 0 || self%(p+6)  == 0 || self%(p+10) == 0 ||
          self%(p+12) == 0 || self%(p+16) == 0 || self%(p+22) == 0 || self%(p+24) == 0
      end
      true
    end

prime_division(generator = Prime::Generator23.new) click to toggle source

Returns the factorization of `self`.

See `Prime#prime_division` for more details.

                   # File prime.rb, line 29
    def prime_division(generator = Prime::Generator23.new)
      Prime.prime_division(self, generator)
    end