This paper presents hardware d~igns, arithmetic algorithms, and numerical applicmions for variableprecision, interv:il arithmetk coproces.~rs. These copr~mes.,~ms give the programmer the ability to ~ the initial precision of the comptttation, determine the accuracy of the results, and recomput¢ inaccttrate r~ults with higher precision. Variable-precision, interval arithmetic algorithms are used to reduce the execution times of numeric,'al applications. Three hardware designs with data "paths of 16, 3, 9, and 64 bits are examined. These designs are compared based tm their estimated chip area, cycle time, and executi~m times for various numerical appliGltinns. ~lch copl'~es.~r call be inlp[elnentorl on a single chip with a cycle time th:~t is comparable to IEEE double-precision floating point coprocessors. For certain numerical appficatkms, the copr~:es.,~rs ;ire two to |i~tlr orders of magnitude faster than *1 collventiotla] .,~)ftwar¢ package fi~r variable-precision, interval arithmetic.
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