# How to write a column outside the braces in a matrix?

I would like to produce the following matrix : :

My code is below which only produces the matrix without the additional column.

\documentclass{article}
\usepackage{amsmath}

\begin{document}
\begin{equation*}
\mathbf{H}=
\begin{pmatrix}
1 & 2 & 3 & 5\\
1 & 1 & 4 & 2\\
4 & 1 & 2 & 4
\end{pmatrix}
\end{equation*}
\end{document}


One possibility might be to employ blkarray.

\documentclass{article}
\usepackage{blkarray}
\usepackage{amsmath}
\begin{document}
$\begin{blockarray}{(>{\:}cccc<{\:})l} 1 & 2 & 3 & 5 & 10\\ 1 & 1 & 4 & 2 & 10\\ 4 & 1 & 2 & 4 & 10 \\ \end{blockarray}$
\end{document} One possible option is just adding another matrix.

\documentclass{article}
\usepackage{amsmath}

\begin{document}
\begin{equation*}
\mathbf{H}=
\begin{pmatrix}
1 & 2 & 3 & 5\\
1 & 1 & 4 & 2\\
4 & 1 & 2 & 4
\end{pmatrix}
\begin{matrix}
10\\10\\10
\end{matrix}
\end{equation*}
\end{document} • Your solution works in this special case where all matrix cells have the standard height. It doesn't work when the cells contain something like \frac{\frac12}3. – Roland Illig Apr 27 '19 at 13:34
• Sure, LaTeX has many packages for dealing with cases with different complexities, but one should go for the simplest solution first, generalization has its cost! – AboAmmar Apr 27 '19 at 14:17

Considering that matrices are also arrays, I provide a version with basic LaTeX tools: \documentclass{article}
\usepackage{amsmath}

\begin{document}

$\mathbf{H}=\Bigg( \begin{array}{cccc} 1 & 2 & 3 & 5\\ 1 & 1 & 4 & 2\\ 4 & 1 & 2 & 4 \end{array}\Bigg) \begin{array}{c} 10\\ 10\\ 10 \end{array}$

\end{document}


EDIT after the advice of the 2019-10-24 of the author of nicematrix @F. Pantigny reported in the comment.

As another alternative you could add with appropriate modifications using the nicematrix package. For example using the environment {pNiceMatrix} with the option last-col=5.

You can see that you will have the same result as output. \documentclass[12pt]{article}
\usepackage{nicematrix}
\begin{document}
$\mathbf{H}= \begin{pNiceMatrix}[last-col=5] 1 & 2 & 3 & 5 & 10\\ 1 & 1 & 4 & 2 & 10\\ 4 & 1 & 2 & 4 & 10\\ \end{pNiceMatrix}$
\end{document}

• you can delete row with \phantom and than replace pNiceArrayRC with pNiceArrayC and you will obtain the same result :-) – Zarko May 2 '19 at 21:39
• @Zarko Of course. :-) – Sebastiano May 2 '19 at 21:42
• @Zarko Don you know the reason of my downvote? – Sebastiano May 3 '19 at 17:22
• No, I don't know. Your answer not deserve this. Unfortunately I cant up-vote again :-(. – Zarko May 3 '19 at 19:29
• @Sebastino: You should update your answer because {pNiceArrayC} is now deprecated in the package nicematrix. You may use {pNiceArray} with the option last-col instead or even {pNiceMatrix} with the option last-col=5. – F. Pantigny Oct 24 '19 at 19:14