Class | Integer |
In: |
lib/backports/1.8.7/integer.rb
lib/backports/1.9.1/integer.rb lib/backports/1.9.1/stdlib/prime.rb |
Parent: | Object |
magnitude | -> | self |
Re-composes a prime factorization and returns the product.
See Prime#int_from_prime_division for more details.
# File lib/backports/1.9.1/stdlib/prime.rb, line 21 21: def Integer.from_prime_division(pd) 22: Prime.int_from_prime_division(pd) 23: end
Standard in ruby 1.8.7+. See official documentation
# File lib/backports/1.8.7/integer.rb, line 6 6: def even? 7: self[0].zero? 8: end
Standard in ruby 1.8.7+. See official documentation
# File lib/backports/1.8.7/integer.rb, line 11 11: def odd? 12: !even? 13: end
Standard in ruby 1.8.7+. See official documentation
# File lib/backports/1.8.7/integer.rb, line 16 16: def ord 17: self 18: end
Standard in ruby 1.8.7+. See official documentation
# File lib/backports/1.8.7/integer.rb, line 21 21: def pred 22: self - 1 23: end
Returns true if self is a prime number, false for a composite.
# File lib/backports/1.9.1/stdlib/prime.rb, line 33 33: def prime? 34: Prime.prime?(self) 35: end
Returns the factorization of self.
See Prime#prime_division for more details.
# File lib/backports/1.9.1/stdlib/prime.rb, line 28 28: def prime_division(generator = Prime::Generator23.new) 29: Prime.prime_division(self, generator) 30: end
# File lib/backports/1.9.1/integer.rb, line 5 5: def round_with_digits(ndigits=0) 6: ndigits = Backports::coerce_to_int(ndigits) 7: case 8: when ndigits.zero? 9: self 10: when ndigits > 0 11: Float(self) 12: else 13: pow = 10 ** (-ndigits) 14: remain = self % pow 15: comp = self < 0 ? :<= : :< 16: remain -= pow unless remain.send(comp, pow / 2) 17: self - remain 18: end 19: end