Arithmetic on the European Logarithmic Microprocessor

4 November 1999
As an alternative to floating-point, several workers have proposed the use of a logarithmic number system, in which a real number is represented as a fixed-point logarithm. Multiplication and division therefore proceed in minimal time with no rounding error. However, the system can only offer an overall advantage if addition and subtraction can be performed with speed and accuracy at least equal to that of floating-point, but this has hitherto been difficult to achieve. We will present a number of original techniques by which this has now been accomplished. We will then demonstrate by means of simulations that the logarithmic system offers around twofold improvements in speed and accuracy, and finally will describe a new European collaborative project which aims to develop a logarithmic microprocessor during the next three years.
  • Computational Mathematics and Applications Seminar