We will now demonstrate an evaluation of 
,
for 
.
The evaluation of 
proceeds as follows:
,
after specifying which rounding mode is used for each operation.
The evaluation of 
proceeds as follows:
.
There is some freedom in the assignment of rounding modes;
the above is intended as a guide to producing a
valid model, not necessarily an optimal one.
Even with a fixed assignment of rounding modes,
the choice of rounding modes will influence the optimality
of the model, as well as the execution cost.
| Jeff Tupper | March 1996 |