Method: Flt::FormatBase.strict_epsilon

Defined in:
lib/float-formats/classes.rb

.strict_epsilon(sign = +1, round = nil) ⇒ Object

The strict epsilon is the smallest value that produces something different from 1.0 wehen added to 1.0. It may be smaller than the general epsilon, because of the particular rounding rules used with the floating point format. This is only meaningful when well-defined rules are used for rounding the result of floating-point addition. Note that (in pseudo-code):

((1.0+strict_epsilon)-1.0)==epsilon

TODO: use Flt::Num



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# File 'lib/float-formats/classes.rb', line 767

def self.strict_epsilon(sign=+1, round=nil)
  round ||= @round
  s = sign
  m = minimum_normalized_integral_significand
  e = 2*(1-significand_digits)
  # assume radix is even
  case @round
  when :down, :floor, :any_rounding, nil
    e = 2*(1-significand_digits)
    m = minimum_normalized_integral_significand
  when :half_even, :half_down
    e = 1-2*significand_digits
    m = 1 + radix_power(significand_digits)/2
  when :half_up
    e = 1-2*significand_digits
    m = radix_power(significand_digits)/2
  when :ceiling, :up, :up05
    return min_value
  end
  return_value sign,m,e

end