Class: Integer

Inherits:
Object show all
Defined in:
lib/lite/ruby/integer.rb

Constant Summary collapse

ROMAN_NUMERALS = 
YAML.load_file(
  File.expand_path('formats/integer_roman_numerals.yml', File.dirname(__FILE__))
).freeze
SQL_SMALLINT = 
32_767
SQL_INTEGER = 
2_147_483_647
SQL_BIGINT = 
9_223_372_036_854_775_807

Instance Method Summary collapse

Instance Method Details

#bit(bit) ⇒ Object 



15
16
17
18
19
20
21
22
23
 
# File 'lib/lite/ruby/integer.rb', line 15

def bit(bit)
  if bit.negative?
    mask = (1 << ~bit)
    self & ~mask
  else
    mask = (1 << bit)
    self | mask
  end
end

#bit?(bit) ⇒ Boolean

Returns:

  • (Boolean) 


25
26
27
28
 
# File 'lib/lite/ruby/integer.rb', line 25

def bit?(bit)
  mask = (1 << bit)
  (self & mask) != 0
end

#bit_clear(bit) ⇒ Object 



30
31
32
33
 
# File 'lib/lite/ruby/integer.rb', line 30

def bit_clear(bit)
  mask = (1 << bit)
  self & ~mask
end

#bitmask(mask) ⇒ Object 



35
36
37
38
39
40
41
 
# File 'lib/lite/ruby/integer.rb', line 35

def bitmask(mask)
  if mask.negative?
    self & mask
  else
    self | mask
  end
end

#bitmask?(mask) ⇒ Boolean

Returns:

  • (Boolean) 


43
44
45
 
# File 'lib/lite/ruby/integer.rb', line 43

def bitmask?(mask)
  (self & mask) != 0
end

#combinatorial(num) ⇒ Object 



47
48
49
 
# File 'lib/lite/ruby/integer.rb', line 47

def combinatorial(num)
  (0...num).inject(1) { |acc, i| (acc * (self - i)) / (i + 1) }
end

#factorial ⇒ Object 



51
52
53
 
# File 'lib/lite/ruby/integer.rb', line 51

def factorial
  (1..self).inject { |acc, i| acc * i } || 0
end

#factors ⇒ Object 



55
56
57
58
59
60
61
62
63
64
65
 
# File 'lib/lite/ruby/integer.rb', line 55

def factors
  limit = Math.sqrt(self).floor

  (1..limit).each_with_object([]) do |i, array|
    next unless (self % i).zero?

    sq = (self / i)
    array.push(i)
    array.push(sq) if sq != i
  end
end

#of(&block) ⇒ Object 



67
68
69
 
# File 'lib/lite/ruby/integer.rb', line 67

def of(&block)
  Array.new(self, &block)
end

#roman_numeral ⇒ Object 



71
72
73
74
75
76
 
# File 'lib/lite/ruby/integer.rb', line 71

def roman_numeral
  return '' if zero?
  return "-#{(-self).roman_numeral}" if negative?

  ROMAN_NUMERALS.each { |key, val| break "#{key}#{(self - val).roman_numeral}" if val <= self }
end

#to_time ⇒ Object Also known as: to_t 



78
79
80
 
# File 'lib/lite/ruby/integer.rb', line 78

def to_time
  Time.at(self)
end