Re: [NTG-context] Sum and mathalignment

30 Nov 2021

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On 30 Nov 2021, at 19:34, Alexandre Christe via ntg-context  wrote:
Dear list,

What I've done is to play with mathalignment and \framed. Here is a MWE:
\starttext
\defineoverlay[midrule][{\blackrule[height=.02cm,width=5.5cm]}]
\framed[frame=off,background=midrule,boffset=.65cm]{\startformula
  \startmathalignment[n=12,align={middle,middle,middle,middle,middle,middle,middle,middle,middle,middle,middle,middle}]
    \NC \NC S_6 \NC= \NC 1 \NC+ \NC 2 \NC+ \NC\dots \NC+ \NC 5 \NC+ \NC 6 \NR
    \NC + \NC S_6 \NC= \NC 6 \NC+ \NC 5 \NC+ \NC\dots \NC+ \NC 2\NC+ \NC 1 \NR
    \NC\NC 2S_6 \NC= \NC 7 \NC+ \NC 7 \NC+ \NC\dots \NC+ \NC 7 \NC+ \NC 7 \NR
  \stopmathalignment
\stopformula}
\stoptext
Is there a simpler way to typeset something like this?
How about:

\usecolors[svg]
\starttext
\ssa\bold
\starttabulate[|r|CT{red}c|c|CT{yellow}c|c|CT{green}c|c|CT{cyan}c|c|CT{blue}c|c|CT{darkmagenta}c|]
    \NC   S = \NC 1 \NC + \NC 2 \NC + \NC 3 \NC + \NC 4 \NC + \NC 5 \NC + \NC 6 \NC\NR
    \NC + S = \NC 6 \NC + \NC 5 \NC + \NC 4 \NC + \NC 3 \NC + \NC 2 \NC + \NC 1 \NC\NR
    \HL[cornflowerblue]
    \NC  2S = \NC 7 \NC + \NC 7 \NC + \NC 7 \NC + \NC 7 \NC + \NC 7 \NC + \NC 7 \NC\NR
\stoptabulate
\stoptext

—
Bruce Horrocks
Hampshire, UK