module BitsCount::Primitive
Constants
- UNPACK_PATTERN
- WORDBITS
Public Class Methods
population_count_int32(i)
click to toggle source
# File lib/bits_count/primitive.rb, line 8 def population_count_int32(i) i = i - ((i >> 1) & 0x55555555) i = (i & 0x33333333) + ((i >> 2) & 0x33333333) i = (i + (i >> 4)) & 0x0F0F0F0F i = i + (i >> 8) i = i + (i >> 16) i & 0x0000003F end
population_count_map(i)
click to toggle source
# File lib/bits_count/primitive.rb, line 22 def population_count_map(i) WORDBITS[i&0xFFFF] + WORDBITS[i>>16] end
population_count_str(s)
click to toggle source
# File lib/bits_count/primitive.rb, line 18 def population_count_str(s) s.unpack(UNPACK_PATTERN).first.count(?1) end