Generating Random Numbers with FOCAL

FOCAL8-188

W. Siegel, K. Whittle and J. Siegel, University of Western

Ontario, London, Canada

This program provides a patch to correct the problem with

FOCAL's random number generator. This routine uses an

algorithm developed by Green, Smith and Klem (1959) which

has several advantages for use with minicomputers. First,

unlike most such generators, it uses an addative rather than a

multiplicative process; addition is much faster than multipli-

cation with most machines. Second, the routine is relatively

short and third, it has been documented and tested and its

characteristics are known. A listing for the patch for FOCAL-

12 is provided, but other versions of FOCAL may be modified

with similar changes. Three short general programs are in

cluded which type out sequences of random integers.

Minimum Hardware:
PDP-8 or PDP-12

Other Programs Needed:
FOCAL, FOCAL-12

Source Language:
Assembly Language

Catalog: July 1973