Patent · US Expired

Calculator for calculating a.sup.x with the base a of any positive number by calculating common logarithm of a

US4158889A · kind A · utility

6Cited by
2References
6Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 8, 1978
Grant dateJun 19, 1979
Priority date
Expiry dateFeb 8, 1998

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F7/556
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A calculator for calculating a.sup.x with the base a of an optional positive number comprises a first circuit for calculating log.sub.10 a. A multiplier calculates x.multidot.log.sub.10 a,which is separated into an integral part z.sub.i and a fractional part z.sub.f. The integer z.sub.i represents the place of the decimal point in the desired result. A second circuit calculates 10.sup.z .sbsp.f which gives the desired result as a number equal to or greater than unity and smaller than ten. The number is stored in a register without the decimal point. With the decimal point put as indicated by the integer z.sub.i, the number gives the desired result. A second circuit may comprise a combination of operation registers, a multiplier, and an adder for calculating the power by combination of multiplication and addition.

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