> L.S.-Soc&Gam <mailto:axteffekt@gmail.com>
> 10. April 2016 um 02:33
> Hi guys,
>
> i've already searched the mailing list for this but i still am having 
> a problem while trying to create a matrix.
> my code looks like this:
>
> \startformula
> S=\left(*\matrix**{*
>   \sigma_x *&* \tau_{xy} *&* \tau_{xz} *\cr*
>   \tau_{yx} *&* \sigma_y *&* \tau_{yz} *\cr*
>     \tau_{zx} *&* \tau_{zy} *&* \sigma_z *\cr*
> *}*\right)_{xyz}
> \stopformula
>
> But since a few days, there are only empty braces after compilation. 
> The funny thing is, i worked already. but i've updated context at 
> least once since (only 5 days ago, betas included) and since then 
> after compiling there are only empty braces. When i enter
>
> \startformula
> S=\left(
> 1234
> \right)_{xyz}
> \stopformula
>
> the 1234 shows fine between the braces. so it seems to have to do with 
> \matrix command in some way...
> i don't know any alternative way to create a matrix. any help would be 
> appreciated.
Your code works fine here but I suggest to use ConTeXt’s own matrix 
environment.

\starttext

\startformula
S =    \startmathmatrix[left=\left(,right=\right)]
     \NC \sigma_{x} \NC \tau_{xy}  \NC \tau_{xz}  \NR
     \NC \tau_{yx}  \NC \sigma_{y} \NC \tau_{yz}  \NR
     \NC \tau_{zx}  \NC \tau_{zy}  \NC \sigma_{z} \NR
     \stopmathmatrix_{xyz}
\stopformula

\stoptext

Wolfgang