# Matrix and vertical lines in columns

Can someone please tell me how I get vertical lines in the columns of a matrix like it is shown in the picture?

I started with ... = \begin{pmatrix} \lambda A' & \mu B' & \tau C' \end{pmatrix} ...

You could use a \vline

\documentclass{article}
\usepackage{amsmath}
\begin{document}

$M = \begin{pmatrix} \vline & \vline & \vline \\ \lambda A' & \mu B' & \tau C' \\ \vline & \vline & \vline \end{pmatrix}$
\end{document}

• Glad it helped! If this answer or any other one solved your issue, please consider to mark it as accepted. – Source Aug 6 '18 at 10:08

Use \mid as ordinary table entry.

\documentclass{article}
\usepackage{amsmath}
\begin{document}
$M = \begin{pmatrix} \mid & \mid & \mid \\ \lambda A' & \mu B' & \tau C' \\ \mid & \mid & \mid \end{pmatrix}$
\end{document}