# [OS X TeX] Cancelling columns?

Alain Matthes alain.matthes at mac.com
Sat Mar 22 04:47:28 EDT 2008

Le 21 mars 08 à 02:50, David Derbes a écrit :

> I apologize for what is probably a simple thing, but it's defeated
> me for a while now.
>
> I am writing a small note about calculation of determinants using
> minors. I would like to draw explicitly a line through the numbers
> of a row

not a good idea but "for me", I prefer to use boxes like below but
It' s possible to draw a line with TikZ and matrix node like you want

\documentclass[]{article}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{amsmath}
\usepackage{tikz}
\usetikzlibrary{matrix}

\begin{document}

\begin{tikzpicture}
\matrix (magic) [matrix of nodes]
{
8 & 1 & 6 \\
3 & 5 & 7 \\
4 & 9 & 2 \\
};
\draw[thick,red,-] (magic-1-2.north) -- (magic-3-2.south);
\end{tikzpicture}

\end{document}

> (which I think I can do with the soul'' package.) But how to do it
> with a column? If worse comes to worse, I can use LaTeXiT to export
> the matrix to Illustrator, draw the lines in Illustrator, and then
> use it as a graphic. But if LaTeX will do the job, I'd prefer that.
>

Perhaps you can try something like the code below :

From MathMode.pdf by Herbert Voss .

\documentclass[]{article}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{amsmath}

\begin{document}
$\left( \begin{array}{c@{}c@{}c} \begin{array}{|cc|} \hline a_{11} & a_{12} \\ a_{21} & a_{22} \\ \hline \end{array} & 0 & 0 \\ 0 & \begin{array}{|ccc|} \hline b_{11} & b_{12} & b_{13}\\ b_{21} & b_{22} & b_{23}\\ b_{31} & b_{32} & b_{33}\\ \hline \end{array} & 0 \\ 0 & 0 & \begin{array}{|cc|} \hline c_{11} & c_{12} \\ c_{21} & c_{22} \\ \hline \end{array} \\ \end{array} \right)$

$\overrightarrow{A}=\left[ \begin{array}{cccc} 1 & 2 & 3 & 4\\ 1 & 2 & 3 & 4\\\hline \multicolumn{1}{|c}{1} & 2 & 3 & \multicolumn{1}{c|}{4}\\\hline 1 & 2 & 3 & 4 \end{array}\right]$

$\overrightarrow{A}=\left[ \begin{array}{cc|c|c}\cline{3-3} 1 & 2 & 3 & 4\\ 1 & 2 & 3 & 4\\ 1 & 2 & 3 & 4\\ 1 & 2 & 3 & 4\\\cline{3-3} \end{array}\right]$

$\overrightarrow{A}=\left[ \begin{array}{cc|c|c}\cline{3-3} 1 & 2 & 3 & 4\\ 1 & 2 & 3 & 4\\\hline \multicolumn{1}{|c}{1} & 2 & 3 & \multicolumn{1}{c|}{4}\\\hline 1 & 2 & 3 & 4\\\cline{3-3} \end{array}\right]$
\end{document}

Best Regards

Alain Matthes