Dear Mr. and Mrs. GAP,
I just want to let you know about a few bugs in the function
DisplayCharTable(). I have not yet installed the latest version
of gap, so perhaps you have already fixed them.

I have found three bugs:

1. Some tables cause alignment problems in output. I believe this is
because widths are not computed correctly. The follwing commands will
exhibit this bug in the third page out the displayed character table:

gap> grp :=CyclicGroup(AgWords,48);
Group( c48_1, c48_2, c48_3, c48_4, c48_5 )
gap> tbl := CharTablePGroup(grp);;
gap> DisplayCharTable(tbl);

2. Not all of the features work. The manual page claims that one
may select certain characters or a character to display. I have
found that this only works for a list which begins with 1.
I have illustrated this twice in the follwing session.

gap> arec := rec( chars:= 5); DisplayCharTable(tbl,arec);
rec(
  chars := 5 )

Error, List Element: <list>[5] must have a value at
charvals[i][cc] := stringEntry( chars[i][cc] ) ... in
DisplayCharTable( tbl, arec ) called from
main loop
brk> quit;

gap> arec := rec( chars:= [5]); DisplayCharTable(tbl,arec);
rec(
  chars := [ 5 ] )

Error, List Element: <list>[5] must have a value at
charvals[i][cc] := stringEntry( chars[i][cc] ) ... in
DisplayCharTable( tbl, arec ) called from
main loop
brk> quit;

---But this works:

gap> arec := rec( chars:= [1..5]); DisplayCharTable(tbl,arec);

3. The same errors occur when one trys to select particular
classes as the manual claims you should be able to. Illustrated
below:

gap> arec := rec( chars:= [2..5]); DisplayCharTable(tbl,arec);
rec(
  chars := [ 2 .. 5 ] )

Error, List Element: <list>[5] must have a value at
charvals[i][cc] := stringEntry( chars[i][cc] ) ... in
DisplayCharTable( tbl, arec ) called from
main loop
brk> quit;

gap> arec := rec( classes := 2); DisplayCharTable(tbl,arec);
rec(
  classes := 2 )

Error, Length: <list> must be a list at
ncols := Length( classes ) + 1 ... in
DisplayCharTable( tbl, arec ) called from
main loop
brk> quit;
gap> arec := rec( classes := [2..4]); DisplayCharTable(tbl,arec);
rec(
classes := [ 2 .. 4 ] )

Error, List Element: <list>[2] must have a value at
len := Length( charvals[i][col] ) ... in
colWidth( classes[col + acol - 1] ) called from
DisplayCharTable( tbl, arec ) called from
main loop
brk> quit;

------ But this works:

gap> arec := rec( classes := [1..4]); DisplayCharTable(tbl,arec);

I hope this helps. I use gap all the time, and really appreciate the work
you folks are doing. I'm sorry I am unable to provide fixes for these bugs.

Peter Blanchard