Patent · US Expired

Bipartite look-up table with output values having minimized absolute error

US6223192A · kind A · utility

26Cited by
3References
32Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 16, 1998
Grant dateApr 24, 2001
Priority date
Expiry dateJun 16, 2018

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F2207/3828
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A method for generating entries for a bipartite look-up table having base and difference table portions. In one embodiment, these entries are usable to form output values for a mathematical function, f(x), in response to receiving corresponding input values within a predetermined input range. The method first comprises partitioning the input range into I intervals, J subintervals/interval, and K sub-subintervals/subinterval. For a given interval M, the method includes generating K difference table entries and J base table entries. Each of the K difference table entries corresponds to a particular group of sub-subintervals within interval M, each of which has the same relative position within their respective subintervals. Each difference table entry is computed by averaging difference values for the sub-subintervals included in a corresponding group N. Each difference value which makes up this average is equal to f(X1)-f(X2), where X1 is the midpoint of the sub-subinterval within group N, and X2 is the midpoint of a predetermined reference sub-subinterval within the same subinterval as X1. Each of these midpoints is calculated such that maximum absolute error is minimized for all p…

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