draw line between two halves of a tikz matrix easily

Question

\begin{center}\begin{tikzpicture}
  \matrix (m)
    [
      matrix of math nodes,
      row sep    = 3em,
      column sep = 4em
    ]
    {
      1 & 3 \\
      2 & 4\\
    };
\end{tikzpicture}\end{center}

I'd like to draw a vertical line to separate the two sides of the matrix. I realize one can extend the matrix and such but I'd rather have something that is a bit more general and doesn't explicitly depend on a bunch of stuff(such as specifying nodes, extending the matrix size, computing mid points using some package, etc). (this way it works for more complex examples).

If the number of columns is even, you can simply do \draw (m.north) -- (m.south);. If not, have a look at my fixed matrix in this answer. — Max, Sep 10 '18 at 12:49
@Max If the number is even and the nodes have all the same widths. — , Sep 10 '18 at 12:50
Here you can find macros that do that. It is the same trick as in Zarko's answer, but done some months ago... — , Sep 10 '18 at 12:54

score 2 · Accepted Answer · answered Sep 10 '18 at 12:52

2

try

\documentclass[tikz, margin=3mm]{standalone}
\usetikzlibrary{calc,
                matrix
                }

\begin{document}
\begin{tikzpicture}
  \matrix (m)
    [
      matrix of math nodes,
      row sep    = 3em,
      column sep = 4em
    ]
    {
      X & A \\
      Y & B\\
    };
  \draw ($(m-1-1.north east)!0.5!(m-1-2.north west)$) -- ($(m-2-1.south east)!0.5!(m-2-2.south west)$);
\end{tikzpicture}
\end{document}

answered Sep 10 '18 at 12:52

Zarko

296,517

This trick has already been used here and perhaps before. When I wrote that answer, I couldn't find an earlier post, but that does not mean much. – Sep 10 '18 at 12:56
@marmot, i know that i didn't discover a wheel, it exist very long time :-). i accidentally had a little free time, so I wrote this simple answer. – Zarko Sep 10 '18 at 13:06

draw line between two halves of a tikz matrix easily

1 Answers1