Bracket (like "cases") around "eqnarray"

#1

Hey,

I’m trying some fancier LaTeX math stuff in TeXmacs and can’t get the following to work:

A bracket around an eqnarray environment. This is how it could look like in LaTeX

19

The example comes from here: https://nmfs-opensci.github.io/quarto-amsmath/fancy_equations.html

I’ve tried to join a whole column in an “eqnarray” but TeXmacs refuses to do this (probably for good reason). It’s possible in a “table” but then I can’t get the curly bracket to span a whole column.

I appreciate your help.

Best,
Heiner

#2

I figured this out. It’s possible using a table inside an equation.

<equation|<around*|\<nobracket\>|few<tabular*|<tformat|<cwith|1|1|4|4|cell-row-span|3>|<cwith|1|1|4|4|cell-col-span|1>|<cwith|1|1|4|4|cell-valign|c>|<cwith|1|1|4|4|cell-hyphen|n>|<table|<row|<cell|fef>|<cell|=>|<cell|fewf>|<cell|<around*|\<nobracket\>||}>>|<cell|w>>|<row|<cell|fe>|<cell|=>|<cell|few>|<cell|>|<cell|dw>>|<row|<cell|fe>|<cell|=>|<cell|fwe>|<cell|>|<cell|dw>>>>>|}>Maxwells
equation>

And it looks like this:

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Bildschirmfoto 2026-03-25 um 13.24.58.png1010×121 3.07 KB

I’ve also tried to have multiple lines behind the bracket which are aligned with the lines before the bracket but can’t get the bracket to span the whole column.

Any idea how this could work? This would be the icing on the cake.

Thanks,
Heiner

#3

grafik

I did it in this way:

  1. making a table of one row, three columns
  2. inserting curly braces in the first and last column
  3. inserting a table inside the curly braces in each column, each table one column, three rows
  4. typing equations
  5. adding in each cell the vertical phantom of the contents of the corresponding cell of the other table
<\equation*>
  <tabular|<tformat|<table|<row|<cell|<around*|\<nobracket\>|<tabular|<tformat|<table|<row|<cell|e=p<vphantom|r=<frac|d|k>>>>|<row|<cell|b=<frac|q|c><vphantom|c=s>>>|<row|<cell|s=t<vphantom|l=m>>>>>>|}>>|<cell|>|<cell|<around*|\<nobracket\>|<tabular|<tformat|<table|<row|<cell|<vphantom|e=p>r=<frac|d|k>>>|<row|<cell|<vphantom|b=<frac|q|c>>c=s>>|<row|<cell|<vphantom|s=t>l=m>>>>>|}>>>>>>
</equation*>

It is a hack. The picture I attached shows a grid superposed to the table construction and it seems to me that the equal signs are aligned.
I wonder if there is a “structural” solution.

#4

Thanks, thought about a visual phantom as well. Not perfect but definitely a solution for such an occasional edge case.