Hi Hans,
If I do this, the problem remains the same.

\starttikzpicture
  \vbox{\matrix [matrix of math nodes,ampersand replacement=\&]
  {
    a_8 \& a_1 \& a_6         \\
    a_3 \& a_5 \& |[red]| a_7 \\
    a_4 \& a_9 \&     a_2     \\
  };}
\stoptikzpicture


2016-07-21 11:38 GMT+02:00 Hans Hagen <pragma@wxs.nl>:
On 7/21/2016 11:25 AM, Fabrice Couvreur wrote:
Hello,
Everything is in the title, as this example shows.

normally it means that you need to wrap in a \vbox{...}

Thanks,
Fabrice


####################################################################
\usemodule[tikz]
\usetikzlibrary[matrix]

\setupbodyfont[pagella,11pt]

\starttext

\starttikzpicture
  \matrix [matrix of math nodes,ampersand replacement=\&]
  {
    a_8 \& a_1 \& a_6         \\
    a_3 \& a_5 \& |[red]| a_7 \\
    a_4 \& a_9 \&     a_2     \\
  };
\stoptikzpicture

\stoptext

####################################################################
tex error       > tex error on line 14 in file /home/fab/ntg49.tex: !
Argument of \tikz@lib@matrix@with@options has an extra }

<inserted text>
\par
<to be read again>
}
l.14   }
      ;

 4     \setupbodyfont[pagella,11pt]
 5
 6     \starttext
 7
 8     \starttikzpicture
 9       \matrix [matrix of math nodes,ampersand replacement=\&]
10       {
11         a_8 \& a_1 \& a_6         \\
12         a_3 \& a_5 \& |[red]| a_7 \\
13         a_4 \& a_9 \&     a_2     \\
14 >>    };
15     \stoptikzpicture
16
17     \stoptext




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___________________________________________________________________________________
If your question is of interest to others as well, please add an entry to the Wiki!

maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context
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archive  : http://foundry.supelec.fr/projects/contextrev/
wiki     : http://contextgarden.net
___________________________________________________________________________________