Re: [NTG-context] Simple command with variable number of arguments

Dear Luigi and listers, Last year, I need to write a text for a linear algebra class. Since there are many \startmatrix … \stopmatrix and matrix calculations, I wrote a lua code which did matrix calculations and writing with a lot of help from this list. Using the code, I can write class materials easily. It is good enough for my purpose. I am not good in Lua coding, so there may be many things to be checked for efficiency and for stability. However, I attached the code because there may be someone who need it. It is also good thing to return what I get from the list back. I hope that you enhance the code for better performance since you are an expert in Lua. I always thank to this list and to developers of ConTeXt. Best regards, Dalyoung

Message: 1 Date: Fri, 23 May 2014 13:44:30 +0200 From: luigi scarso To: mailing list for ConTeXt users Subject: Re: [NTG-context] Simple command with variable number of arguments Message-ID: Content-Type: text/plain; charset="utf-8"

On Fri, May 23, 2014 at 11:54 AM, Matthias Weber 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,

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

\startluacode document = document or {} document.matthias = document.matthias or {} local function lua_columnvector(a) context.startpmatrix() for i,v in ipairs(a) do context.NC() context(tostring(v)) context.NR() end context.stoppmatrix() end document.matthias.lua_columnvector = document.matthias.lua_columnvector or lua_columnvector \stopluacode

\def\columnvector#1{\ctxlua{document.matthias.lua_columnvector(#1)}}

\starttext \startformula \columnvector{{1,2,3}} %% watch the double { ! \stopformula

\stoptext

-- luigi