Class: Float

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

Instance Method Summary collapse

Instance Method Details

#to_d ⇒ void

This method returns an undefined value.

Raises a ‘TypeError` exception. The reason this method is defined at all is to produce a more meaningful error than `NoSuchMethod`.

Raises:

  • (TypeError) 


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# File 'lib/ruby/to_d.rb', line 69

def to_d
  # The problem is there isn't a way to know the correct precision,
  # since there are (many) values that cannot be represented exactly
  # using Floats. For instance, we can't assume which value is correct
  #
  #   "%0.10f" % 1.8 #=> "1.8000000000"
  #   "%0.20f" % 1.8 #=> "1.80000000000000004441"
  #
  # The programmer should convert the Float to a String using whatever
  # precision he chooses, and call #to_d on the String.
  raise TypeError, "cannot convert Float to BigDecimal"
end