Thanks Otared,

that looks very promising. My attempt to wrap the arguments with \NC \NR fails, though.
It looks like only the first argument is used, and I am clearly missing something.
Also, I’d like to use the example you posted but without the last comma so that in the example below
I get (4,5) instead of (4,5,).

Matthias


\definemathmatrix
  [pmatrix]
  [left={\left(\,},right={\,\right)}]
  

\def\docolumnvector#1{\NC#1\NR}
  
\def\columnvector#1
{\startpmatrix
\processcommalist[#1]\docolumnvector
\stoppmatrix}


\def\dorowvector#1{#1,}
  
\def\rowvector#1
{\startpmatrix
\processcommalist[#1]\dorowvector
\stoppmatrix}

\starttext

\startformula
\columnvector{1,2,3}
\stopformula

\startformula
\rowvector{4,5}
\stopformula

\stoptext





On May 23, 2014, at 6:08 AM, Otared Kavian <otared@gmail.com> wrote:

> Hi,
> 
> Some time ago Wolfgang S. gave a solution to a similar problem: maybe this can help you.
> 
> %%%% begin
> \def\somemacro#1%
>  {\def\dosomemacro##1{Execute ##1, }%
>   \processcommalist[#1]\dosomemacro}
> 
> \starttext
> \somemacro{A,B,C}
> 
> \somemacro{E,F}
> \stoptext
> %%%% end
> 
> Best regards: OK
> 
> On 23 May 2014, at 11:54, Matthias Weber <matweber@indiana.edu> wrote:
> 
>> Dear All,
>> 
>> I would like to define a command that expands 
>> 
>> \vector{2,4} % or vector[2,4] if that’s easier
>> 
>> to
>> 
>> \startpmatrix
>> \NC 2 \NR
>> \NC 4 \NR
>> \stoppmatrix
>> 
>> and more generally
>> 
>> \vector{2,4,1,7}
>> 
>> to
>> 
>> \startpmatrix
>> \NC 2 \NR
>> \NC 4 \NR
>> \NC 1 \NR
>> \NC 7 \NR
>> \stoppmatrix
>> 
>> Any hints how to achieve this?
>> 
>> Thanks,
>> 
>> Matthias
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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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> ___________________________________________________________________________________