# 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 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 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}


As another alternative you could add with appropriate modifications using the nicematrix package. For example the environment {pNiceArrayC} (thank you very much for the suggestion of @Zarko (see comment)) add a matrix with an exterior column.

You can get the same result as the starting image and the other answers.

\documentclass{article}
\usepackage{nicematrix}
\begin{document}
$\mathbf{H}=\begin{pNiceArrayC}{CCCC} 1 & 2 & 3 & 5 & 10\\ 1 & 1 & 4 & 2 & 10\\ 4 & 1 & 2 & 4 & 10\\ \end{pNiceArrayC}$
\end{document}

• you can delete row with \phantom and than replace pNiceArrayRC with pNiceArrayC and you will obtain the same result :-) – Zarko May 2 at 21:39
• @Zarko Of course. :-) – Sebastiano May 2 at 21:42
• @Zarko Don you know the reason of my downvote? – Sebastiano May 3 at 17:22
• No, I don't know. Your answer not deserve this. Unfortunately I cant up-vote again :-(. – Zarko May 3 at 19:29
• @Zarko I am not very expert of LaTeX but I have understood, many times, because I receveid severals downvotes without an explanation. I am very interesting to increase my experience in LaTeX and I'm not interesting for votes. Thank you very much always. Bye. – Sebastiano May 3 at 19:32