To anyone who is familiar with the expert system "PC-PLUS".
The source code of Pc-Plus is written in SCHEME ,which is
very similar to LISP.
We are trying to call external functions and there are several
ways to do that :
(1) using "DOS-CALL" to call a function in DOS.
The external functions are written in BASIC.
Our problem is that we can't send parameters to the
external programs.
We can activate the external functions but then we have
to re-enter the values.
e.g. IF bla bla bla
THEN bla bla bla AND DOS-CALL "drive:filename.EXE"
" var1 var2 ... varN "
The stand-alone EXE file was made by using QBASIC.
After the program was run (in the PC-PLUS environment)
the screen got messed up pretty badly. The graphics and
text were all "smuched".
(2) another method is re-write all the programs in LISP .
The source code can be compiled using the EDWIN editor.
The problems with this mehtod are :
(a)converting the basic program to LISP
10 input cut_off_freq, q_factor
20 if cut_off_freq < 1000 then c1=1e-08
30 if cut_off_freq => 1000 and < 10000 then c1=1e-09
40 if cut_off_freq =>10000 and < 50000 then c1=1e-10
50 if cut_off_freq => 50000 then c1=1e-11
60 c2 = c1
70 c3 = 2 * c1
80 r1 = 1/(4 * pi * cut_off_freq * c1)
90 r2 = .......
100 r3 = .......
110 end
The output screen contains a circuit schematic as well as
the results of the program above.
The above program has TWO inputs and SIX variables.
c1 is dependent on the cut_off_freq. When I wrote this in
LISP it says the variables are not defined in the lexical
environment, PLEASE HELP!!!
(b) we can't get the LISP function to accept the values
send it either. We wrote a simple program to test
that.
I would very much to set up a personal contact with anyone who
can help us. THE EXPERT SYSTEM IS WRITTEN IN PCSCHEME 3.01.
PLEASE RESPONSE SOON . THANK YOU .
Boon Keong Teng. South Australian Institute of Technology.
From: Vincent Manis
Subject: Re: Looking for help with PC-PLUS
Date:
Message-ID: <7671@ubc-cs.UUCP>
I would strongly recommend sitting down with a textbook on Scheme
programming (Jerry Smith's `An Introduction to Scheme' [Prentice-Hall]
might be right for you). After having learned Scheme, you will have no
trouble translating your Basic code into Scheme procedures. That, rather
than using DOS-CALL, is the preferred way of doing things.
--
\ Vincent Manis <·····@cs.ubc.ca> "There is no law that vulgarity and
\ Department of Computer Science literary excellence cannot coexist."
/\ University of British Columbia -- A. Trevor Hodge
/ \ Vancouver, BC, Canada V6T 1W5 (604) 228-2394