Underflow

1 definition found

From The Free On-line Dictionary of Computing (27 SEP 03) [foldoc]:

  underflow
       
           (or "floating point underflow", "floating
          underflow", after "{overflow}") A condition that can occur
          when the result of a {floating-point} operation would be
          smaller in magnitude (closer to zero, either positive or


          negative) than the smallest quantity representable.  Underflow
          is actually (negative) {overflow} of the {exponent} of the
          {floating point} quantity.  For example, an eight-bit {twos
          complement} exponent can represent multipliers of 10^-128 to
          10^127.  A result less than 10^-128 would cause underflow.
       
          Depending on the {processor}, the programming language and the
          {run-time system}, underflow may set a status bit, raise an
          {exception} or generate a {hardware} {interrupt} or some
          combination of these effects.  Alternatively, it may just be
          ignored and zero substituted for the unrepresentable value,
          though this might lead to a later {divide by zero} error which
          cannot be so easily ignored.
       
          (1997-08-25)