pratt@paul.rutgers.edu (Lorien Y. Pratt) (03/14/89)
I am working through the ``cs'' program in PDP, volume 3, and I have found, in
the example on page 67, that pattern files are not being read in correctly.
Every entry is read as a 1.
Can anyone tell me an email address for someone I should contact
about obtaining patches for the PDP3 code in general, and this bug in
particular?
I see that there's a snailmail address at MIT press, but I'd like to avoid
receiving bug fixes on paper, if at all possible!
Thanks in advance for your help,
--
-------------------------------------------------------------------
Lorien Y. Pratt Computer Science Department
pratt@paul.rutgers.edu Rutgers University
Hill Center
(201) 932-4634 New Brunswick, NJ 08901marcoz@MARCOZ.BOLTZ.CS.CMU.EDU (Marco Zagha) (03/17/89)
Here is a list of bug fixed for the PDP volume 3 software
from Jay McClelland (posted with permission).
DO NOT CONTACT ME WITH FURTHER BUGS!!!!
I am not maintaining the software.
== Marco (marcoz@cs.cmu.edu)
-----------------------------------------------------------------
CHANGES TO PDP SOFTWARE AND HANDBOOK
For the second printing of the book "Explorations in parallel
distributed processing: A handbook of models, programs
and exercises", by J. L. McClelland and D. E. Rumelhart,
a small number of changes to the PDP software
have been made, and version 1.1 of the software has
been constructed.
The changes to the software are all either bug fixes or
minor cosmetic changes. The most important fixes
resolve a set of related problems with constraints
on weights in the bp program: In the old version,
chaos could result when weights were linked
together if the network contained more than 100 units,
or if more than 100 weights were linked together
or constrained to be positive or negative.
The necessary changes are all in the file weights.c,
and are listed below.
In addition to the changes to the sources, a few errors
in the handbook text have been detected, and many of these
errors have been corrected in the second printing.
The bp template file cas.tem has also been changed to
allow logging of activations to occur as described in
the handbook text.
Here is a description of the changes to the source files,
followed by the results of running the unix diff program
on the old and new versions. Then a diff of the old
and new versions of bp/cas.tem is provided. Following this,
the errors in the text of the handbook are described.
At the very end, fixes for new problems that have arisen
with Version 1.1 are described.
DESCRIPTION OF CHANGES TO SOURCE FILES
in all .c files:
removed "(void)" cast on all calls to install_var and
install_command. (these functions are now declared as void
explicitly, see below).
bp.c:
in logistic (lines 217,220):
replaced constant 16.0 with 15.935773
(15.935773 is the number whose logistic is equal
to .99999988, which is retured if 15.935773 is exceeded)
command.c:
declared install_command as void.
in do_command:
the second argument to do_command was usually passed
as a pointer but interpreted by do_command as an integer.
This can lead to problems when pointers and integers have
different sizes. To rectify the problem, do_command now
interprets its second argument as a pointer, than converts
it explicitly to an integer, storing the result in the
integer variable Currrent_Menu, which is then used inside
the body of the do_command function.
in contin_test, do_comfile, and file_error:
cast second argument to do_command as (int *)
in do_comfile:
fixed bug that caused programs to crash
if a return was entered in response to "How many times?"
query.
command.h:
declared install_command as void.
general.c:
in emalloc and erealloc:
caused the program to exit when it runs out of
memory rather than returning a null pointer to
the caller.
main.c:
changed version number to 1.1
deleted "stuct Variable *install_var ();" declaration.
in main:
cast second argument to do_command as (int *)
both times it is called.
variable.c:
declared install_var as void and commented out return statement
in this function.
variable.h:
declared install_var as void here too.
weights.c:
in define_network (line 620):
fixed program to null constraint vectors up to
constraints[i].max rather than nunits.
above enlarge_constraints (old line 787):
added #define CON_INCR 100
in enlarge_constraints:
replaced 100 with CON_INCR throughout
old lines 789,796, replaced '=' with '==' in
conditionals.
added code for nulling fresh portions of
positive_constraints,
negative_constraints,
constraints[i].cvec,ivec
DIFF RESULTS
Here follows a diff of versions 1.0 and 1.1. This diff was
performed after all of the "(void)" casts on calls to
install_var and install_command were deleted from
version 1.0. Only files with changes are listed.
The diff tells what should be done to the old version to
convert it into the new. Lines beginning with < come from
version 1.0, lines beginning with > come from version 1.1.
====================
bp.c
====================
217c217
< if (x > 16.0)
---
> if (x > 15.935773)
220c220
< if (x < -16.0)
---
> if (x < -15.935773)
====================
command.c
====================
50c50
< int current_menu;
---
> int *current_menu;
60c60
< Current_Menu = current_menu;
---
> Current_Menu = (int) current_menu;
62c62
< do_help(str,current_menu);
---
> do_help(str,Current_Menu);
68c68
< if (current_menu == BASEMENU) return(POP);
---
> if (Current_Menu == BASEMENU) return(POP);
75c75
< if ((!Command[i].menutype) || (Command[i].menutype == current_menu)) {
---
> if ((!Command[i].menutype) || (Command[i].menutype == Current_Menu)) {
87c87
< (Command[i].menutype == current_menu)) {
---
> (Command[i].menutype == Current_Menu)) {
101c101
< if( current_menu == DISPLAYMENU) {
---
> if( Current_Menu == DISPLAYMENU) {
104c104
< if ((Command[i].menutype == current_menu)) {
---
> if ((Command[i].menutype == Current_Menu)) {
123c123
< (Command[i].menutype == current_menu)) {
---
> (Command[i].menutype == Current_Menu)) {
260c260,264
< install_command(str, func, menu, intp)
---
> /* declare this as void so we don't have to cast all calls to install_command
> abh - 2/15/88
> */
>
> void install_command(str, func, menu, intp)
422c426
< if (do_command(subprompt, BASEMENU) == POP) break;
---
> if (do_command(subprompt, (int *) BASEMENU) == POP) break;
435,436c439,440
< int echeck;
< int nreps,i;
---
> int echeck,i;
> int nreps = 0;
449d452
< nreps = 1;
451c454,458
< sscanf(str,"%d",&nreps);
---
> echeck = 0;
> if (str) echeck = sscanf(str,"%d",&nreps);
> if (echeck == 0) {
> return(put_error("Integer argument missing in do command."));
> }
456c463
< if (do_command(Prompt, BASEMENU) == BREAK) {
---
> if (do_command(Prompt, (int *) BASEMENU) == BREAK) {
492c499
< if (do_command(subprompt, BASEMENU) == BREAK) break;
---
> if (do_command(subprompt, (int *) BASEMENU) == BREAK) break;
====================
command.h
====================
56c56
< int install_command ();
---
> void install_command ();
====================
general.c
====================
79c79
< if (p == 0)
---
> if (p == 0) {
80a81,83
> end_display();
> exit(0);
> }
94c97
< if (p == 0)
---
> if (p == 0) {
95a99,101
> end_display();
> exit(0);
> }
104c110
< if (p == 0)
---
> if (p == 0) {
105a112,114
> end_display();
> exit(0);
> }
====================
main.c
====================
29c29
< char version[10] = "1.0";
---
> char version[10] = "1.1";
36d35
< struct Variable *install_var ();
74c73
< do_command(Prompt, BASEMENU);
---
> do_command(Prompt, (int *) BASEMENU);
94c93
< do_command(Prompt, BASEMENU);
---
> do_command(Prompt, (int *) BASEMENU);
====================
variable.c
====================
55c55
<
---
> /* we replace this:
57c57,60
< install_var (s, t, varptr, max_x, max_y, menutype)
---
> with void to avoid the hassle of casting to void on each call
> abh - 2/15/88
> */
> void install_var (s, t, varptr, max_x, max_y, menutype)
84a88
> /*
85a90
> */
====================
variable.h
====================
31c31
< struct Variable *install_var ();
---
> void install_var ();
====================
weights.c
====================
620c620
< for (j = 0; j < nunits; j++) {
---
> for (j = 0; j < constraints[i].max; j++) {
787a788,789
> #define CON_INCR 100 /* increment in size of constriant */
>
789,790c791,794
< if (con_index = ENLARGE_POS) {
< maxpos += 100;
---
> int j;
>
> if (con_index == ENLARGE_POS) {
> maxpos += CON_INCR;
793c797
< (unsigned int) ((maxpos - 100) * sizeof(float *)),
---
> (unsigned int) ((maxpos - CON_INCR) * sizeof(float *)),
794a799,801
> for (j = maxpos - CON_INCR; j < maxpos; j++) {
> positive_constraints[j] = NULL;
> }
796,797c803,804
< else if (con_index = ENLARGE_NEG) {
< maxneg += 100;
---
> else if (con_index == ENLARGE_NEG) {
> maxneg += CON_INCR;
800c807
< (unsigned int) ((maxneg -100) * sizeof (float *)),
---
> (unsigned int) ((maxneg -CON_INCR) * sizeof (float *)),
801a809,811
> for (j = maxneg - CON_INCR; j < maxneg; j++) {
> negative_constraints[j] = NULL;
> }
804c814
< constraints[con_index].max += 100;
---
> constraints[con_index].max += CON_INCR;
808c818
< ((constraints[con_index].max - 100) * sizeof(float *)),
---
> ((constraints[con_index].max - CON_INCR) * sizeof(float *)),
814c824
< ((constraints[con_index].max - 100) * sizeof(float *)),
---
> ((constraints[con_index].max - CON_INCR) * sizeof(float *)),
816a827,831
> for (j = constraints[con_index].max - CON_INCR;
> j < constraints[con_index].max; j++) {
> constraints[con_index].cvec[j] = NULL;
> constraints[con_index].ivec[j] = NULL;
> }
DIFFERENCES BETWEEN OLD AND NEW VERSIONS OF bp/cas.tem
All of the changes apply only to the dlevel variable:
dlevels of epochno and tss are set to 2 and dlevels of
cpname, cycleno, and output are set to 1. Once again,
the diff indicates how to change the old version
into the new version.
15,17c15,17
< epochno variable 1 $ n epochno 5 1.0
< tss floatvar 1 $ n tss 7 1.0
< cpname variable 2 $ 5 cpname -5 1.0
---
> epochno variable 2 $ n epochno 5 1.0
> tss floatvar 2 $ n tss 7 1.0
> cpname variable 1 $ 5 cpname -5 1.0
19c19
< cycleno variable 2 $ n cycleno 5 1.0
---
> cycleno variable 1 $ n cycleno 5 1.0
27c27
< output vector 2 $ n activation v 3 100.0 2 3
---
> output vector 1 $ n activation v 3 100.0 2 3
ERRATA BY PAGE NUMBER IN THE HANDBOOK [Those marked with *
have been corrected in the second printing]
Page 51: In Equation 2, each pair of units contributes only
one time to the first summation (w sub ij is assumed equal
to w sub ji). The total goodness is not the sum of the goodnesses
of the individual units. It is best to think of the
goodness of unit i as the set of terms in the total
goodness to which the activation of unit i contribues.
*Page 67, lines 6 and 7: Two occurrences of "display/ ipattern"
should read "display/ env".
*Page 85, 2nd line from bottom: The word "two" should be "four".
Page 148, first lines 6 and 10: In both cases the word "left"
should be replaced with the word "right".
*Page 148, 12th line from bottom: The first word on the line,
"weights", should be "bias".
*Page 296, 8th line of Q.4.1.1: The word "input" should be "output".
PROBLEMS IN VERSION 1.1 OF THE SOFTWARE
The file jets.str in the cs directory uses the names 20s 30s and 40s
for three of the units. The names should be changed (by editing the
file) to in20s in30s and in40s respectively. As is these units
names cannot be used because the program interprets them as unit
numbers. NOTE: This only applies to the file jets.str in the cs
directory. The file jets.str in the iac directory is ok as is.
--