Author: G. Chase,

Portsmouth Abbey School, Portsmouth, RI

Source Language: PAL-III

Memory Required: 4K

Other Software Required: FOCAL-8 or FOCAL 5/69

Abstract: These are Mode "B" Extended Arithmetic Element patches

to two versions of the FOCAL language, namely to DEC's FOCAL-8, the

revision of FOCAL, 1969, and to DECUS' FOCAL 5/69 ("Taft" FO-

CAL).

Mode "B" of the EAE is available only on PDP-8/E and later models.

The PDP-12 and the PDP-8/I EAE run in mode "A" only. It is likely that

some parts of the patches might be recodable into mode "A".

The patch to DEC's FOCAL-8 does things to the addition routines as

well as to the floating multiply and divide routines. The other patch

restricts itself to floating multiply and divide only. On a sample program

calculating a lot of arc sines, the FOCAL-8 patch caused the program to

run in about 40% less time than was required with unpatched FOCAL-8;

the TAFT patch saved about 30% as compared with unpatched FOCAL

5/69.

It should be remembered that both languages are interpretive and use

interpretive calls to their floating point packages. A substantial fraction

of the run time of a program is determined simply by the language

structure.

Media Price Code: D2, F5, G 10

Catalog: August 1978