Hi,

I’have a lot of courses notes in MKII. I’m trying to move to MKIV. I have a
problem that I’m not able to resolve, to make a border matrix with
brackets. In MKII, I was using a macro, found somewhere, which works great,
but no longer works; here is the macro:

% Border matrix: first line and column are label
\catcode`\@=11\relax
\newdimen\p@renwd
\font\tenex=cmex10 \setbox0=\hbox{\tenex B} \p@renwd=\wd0
\def\bbordermatrix#1{\begingroup \m@th
\setbox\z@\vbox{\def\cr{\crcr\noalign{\kern2\p@\global\let\cr\endline}}%
    \ialign{$##$\hfil\kern2\p@\kern\p@renwd&\thinspace\hfil$##$\hfil
      &&\quad\hfil$##$\hfil\crcr
      \omit\strut\hfil\crcr\noalign{\kern-\baselineskip}%
      #1\crcr\omit\strut\cr}}%
  \setbox\tw@\vbox{\unvcopy\z@\global\setbox\@ne\lastbox}%
  \setbox\tw@\hbox{\unhbox\@ne\unskip\global\setbox\@ne\lastbox}%
  \setbox\tw@\hbox{$\kern\wd\@ne\kern-\p@renwd\left[\kern-\wd\@ne
    \global\setbox\@ne\vbox{\box\@ne\kern2\p@}%
    \vcenter{\kern-\ht\@ne\unvbox\z@\kern-\baselineskip}\,\right]$}%
  \null\;\vbox{\kern\ht\@ne\box\tw@}\endgroup}
\catcode`\@=12\relax

but MKIV gives me the error:

\bbordermatrix #1->\begingroup \m@th

                                     \setbox \z@ \vbox {\def \cr {\crcr
\noa...

l.26    i & j & k & l \cr}




16       \null\;\vbox{\kern\ht\@ne\box\tw@}\endgroup}

17     \catcode`\@=12\relax

I look for solutions on the list, but did not find anything.Here is a
minimal example:

\starttext
A border matrix:
\startformula
\bbordermatrix{
   a & b & c & d \cr
   e & f & G & h \cr
   i & j & k & l \cr}
\stopformula
\stoptext

As I have in my notes hundreds of such matrix, it is really difficult to
change the input format.

Do you know, or can you point me, to a solution ? I’m in a dead end..
Thanks a lot.
F.