Implementation and Evaluation of Interval Arithmetic Software. Report 4: The IBM 370, DEC 10, and DEC PDP-11/70 Systems

Using interval arithmetic as prescribed in the Interval II package is simple because of the AUGMENT preprocessor. Computer runs illustrate that interval arithmetic can show the instability of an algorithm for a given set of data. On the other hand, interval arithmetic can establish a high level of confidence in an algorithm for a given set of data. Interval arithmetic should be used as any tool would be where accuracy is of critical importance. Interval arithmetic is expensive to use in terms of computer time, main storage, and personnel time spent in error analysis. Some reasonable means of estimating the cost of using interval arithmetic in a given situation should be developed. These costs would be important in the decision process of determining whether or not interval arithmetic would be worth the effort or not. Techniques of accuracy extension on short word length machines should be examined.