code: public static double makeDoubleValue( Object obj )
    {
      if( obj == null )
      {
        return Double.NaN;
      }
  
      return CommonServices.getCoercionManager().makePrimitiveDoubleFrom( obj );
    }
docs: Just like makeDouble(), but creates a double primitive value instead of a
  Double object.  Much more efficient if you don't need the object.
  
  @param obj Any double convertible object
  
  @return The double primitive value.