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I. Koren, O. Zinaty, "Evaluating Elementary Functions in a Numerical Coprocessor Based on Rational Approximations," IEEE Transactions on Computers, vol. 39, no. 8, pp. 10301037, August, 1990.  
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@article{ 10.1109/12.57042, author = {I. Koren and O. Zinaty}, title = {Evaluating Elementary Functions in a Numerical Coprocessor Based on Rational Approximations}, journal ={IEEE Transactions on Computers}, volume = {39}, number = {8}, issn = {00189340}, year = {1990}, pages = {10301037}, doi = {http://doi.ieeecomputersociety.org/10.1109/12.57042}, publisher = {IEEE Computer Society}, address = {Los Alamitos, CA, USA}, }  
RefWorks Procite/RefMan/Endnote  x  
TY  JOUR JO  IEEE Transactions on Computers TI  Evaluating Elementary Functions in a Numerical Coprocessor Based on Rational Approximations IS  8 SN  00189340 SP1030 EP1037 EPD  10301037 A1  I. Koren, A1  O. Zinaty, PY  1990 KW  elementary functions; rational approximations; highprecision floatingpoint numbers; extended double precision format; IEEE standard P754; floatingpoint numeric coprocessor; fast adder; fast multiplier; execution time; silicon area; approximation theory; digital arithmetic; function evaluation; microprocessor chips. VL  39 JA  IEEE Transactions on Computers ER   
A different approach to hardware evaluation of elementary functions for highprecision floatingpoint numbers (in particular, the extended double precision format of the IEEE standard P754) is examined. The evaluation is based on rational approximations of the elementary functions, a method which is commonly used in scientific software packages. A hardware model is presented of a floatingpoint numeric coprocessor consisting of a fast adder and a fast multiplier, and the minimum hardware required for evaluation of the elementary functions is added to it. Next, rational approximations for evaluating the elementary functions and testing the accuracy of the results are derived. The calculation time of these approximations in the proposed numeric processor is then estimated. It is concluded that rational approximations can successfully complete with previously used methods when execution time and silicon area are considered.
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