class Complex

Returns the value as a BigDecimal.

The precision parameter is required for a rational complex number. This parameter is used to determine the number of significant digits for the result.

require 'bigdecimal'
require 'bigdecimal/util'

Complex(0.1234567, 0).to_d(4)   # => 0.1235e0
Complex(Rational(22, 7), 0).to_d(3)   # => 0.314e1

See also Kernel.BigDecimal.

# File bigdecimal-3.1.8/lib/bigdecimal/util.rb, line 157
def to_d(*args)
  BigDecimal(self) unless self.imag.zero? # to raise eerror

  if args.length == 0
    case self.real
    when Rational
      BigDecimal(self.real) # to raise error
    end
  end
  self.real.to_d(*args)
end