Module: Polyfill::V2_5::Integer::ClassMethods

Defined in:
lib/polyfill/v2_5/integer.rb

Instance Method Summary collapse

Instance Method Details

#sqrt(n) ⇒ Object 



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# File 'lib/polyfill/v2_5/integer.rb', line 9

def sqrt(n)
  n = InternalUtils.to_int(n)
  if n < 0
    raise Math::DomainError, 'Numerical argument is out of domain - "isqrt"'
  end

  res = 0
  bit = 1 << ((n.size * 8) - 2)

  bit >>= 2 while bit > n

  while bit != 0
    res_bit = res + bit
    if n >= res_bit
      n -= res_bit
      res = (res >> 1) + bit
    else
      res >>= 1
    end

    bit >>= 2
  end

  res
end