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-rw-r--r--lib/mathn.rb96
1 files changed, 1 insertions, 95 deletions
diff --git a/lib/mathn.rb b/lib/mathn.rb
index ce1acc927f..2af2b83da3 100644
--- a/lib/mathn.rb
+++ b/lib/mathn.rb
@@ -12,101 +12,7 @@
require "complex.rb"
require "rational.rb"
require "matrix.rb"
-
-class Integer
-
- def Integer.from_prime_division(pd)
- value = 1
- for prime, index in pd
- value *= prime**index
- end
- value
- end
-
- def prime_division
- raise ZeroDivisionError if self == 0
- ps = Prime.new
- value = self
- pv = []
- for prime in ps
- count = 0
- while (value1, mod = value.divmod(prime)
- mod) == 0
- value = value1
- count += 1
- end
- if count != 0
- pv.push [prime, count]
- end
- break if prime * prime >= value
- end
- if value > 1
- pv.push [value, 1]
- end
- return pv
- end
-end
-
-class Prime
- include Enumerable
- # These are included as class variables to cache them for later uses. If memory
- # usage is a problem, they can be put in Prime#initialize as instance variables.
-
- # There must be no primes between @@primes[-1] and @@next_to_check.
- @@primes = [2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 101]
- # @@next_to_check % 6 must be 1.
- @@next_to_check = 103 # @@primes[-1] - @@primes[-1] % 6 + 7
- @@ulticheck_index = 3 # @@primes.index(@@primes.reverse.find {|n|
- # n < Math.sqrt(@@next_to_check) })
- @@ulticheck_next_squared = 121 # @@primes[@@ulticheck_index + 1] ** 2
-
- class << self
- # Return the prime cache.
- def cache
- return @@primes
- end
- alias primes cache
- alias primes_so_far cache
- end
-
- def initialize
- @index = -1
- end
-
- # Return primes given by this instance so far.
- def primes
- return @@primes[0, @index + 1]
- end
- alias primes_so_far primes
-
- def succ
- @index += 1
- while @index >= @@primes.length
- # Only check for prime factors up to the square root of the potential primes,
- # but without the performance hit of an actual square root calculation.
- if @@next_to_check + 4 > @@ulticheck_next_squared
- @@ulticheck_index += 1
- @@ulticheck_next_squared = @@primes.at(@@ulticheck_index + 1) ** 2
- end
- # Only check numbers congruent to one and five, modulo six. All others
- # are divisible by two or three. This also allows us to skip checking against
- # two and three.
- @@primes.push @@next_to_check if @@primes[2..@@ulticheck_index].find {|prime| @@next_to_check % prime == 0 }.nil?
- @@next_to_check += 4
- @@primes.push @@next_to_check if @@primes[2..@@ulticheck_index].find {|prime| @@next_to_check % prime == 0 }.nil?
- @@next_to_check += 2
- end
- return @@primes[@index]
- end
- alias next succ
-
- def each
- return to_enum(:each) unless block_given?
- loop do
- yield succ
- end
- end
-end
+require "prime.rb"
class Fixnum
remove_method :/