If we use negative exponents in addition to positive ones, we can also represent which is a small number close to 0. Thus, we can now represent a vastly larger range of numbers with four digits and a sign than before. But, this improvement comes with its own problems. This sign field enables us to represent numbers between 0 and 1 . Because the conditions on the fields of an inex structure are so stringent, we use the function create-inex to create these structures.
Figure contains the function definition for create-inex .
For other numbers, though, we can find two inex equivalents. The appearances, however, are deceiving. In particular, any positive number less than has no equivalent inex structure. Similarly, the inex representation has gaps in the middle. The standard choice is to round the number and to the closest representable equivalent.