The UROUND function converts the  value  of  the  parameter  and
  returns  its unsigned equivalent by rounding the fractional part
  of the value.

  Syntax:

     UROUND( x )

  The parameter 'x' must be  of  type  REAL,  SINGLE,  DOUBLE,  or
  QUADRUPLE.

  No error results if the value of 'x' is negative or greater than
  4,294,967,295.  In that case, the unsigned result is the rounded
  parameter value MOD 4,294,967,296.