• prime.rb

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# 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
```