Patent · US Expired

Apparatus and method for calculating an exponential calculating result of a floating-point number

US6910059B2 · kind B2 · utility

28Cited by
3References
20Claims
0Family size

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Inventors

Key dates

Filing dateJul 9, 2002
Grant dateJun 21, 2005
Priority date
Expiry dateNov 27, 2023

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F2101/10
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

An apparatus for calculating an exponential calculating result for a base 2 floating-point number comprises a transforming device, K exponential tables and a multiplier. The transforming device receives the floating-point number, transforms the floating-point number to an integer part and a fractional part and outputs the integer part and the fractional part. The fractional part is an N-bit number and divided into K parts which have N1, N2, . . . , NK bits respectively, wherein N=N1+N2+ . . . +NK. Each of the exponential tables receives one of the K parts divided from the fractional part and outputs a result. The multiplier receives all results from the exponential tables and outputs a mantissa. The integer part outputted form the transforming device is an exponent. The mantissa, the exponent and a sign whose value is 0 is used to represent an exponential calculating result which is represented in the following format: (−1)Sy·2Ey·my, where Sy is the sign whose value is 0, Ey is the integer part, my is the mantissa and 1≦my<2.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.