Matrix with text besides it behavior weird after equal symbol

I tried to add some text beside a matrix to illustrate it, then I found a solution using package blkarray. Following is the code, and it succeeds to add some text right to the matrix.

$\begin{blockarray}{ccc} \begin{block}{(cc)r} A & B & \text{text one}\\ C & D & \text{text two}\\ \end{block} \end{blockarray}$

$M=\begin{blockarray}{ccc} \begin{block}{(cc)r} A & B & \text{text one}\\ C & D & \text{text two}\\ \end{block} \end{blockarray}$

Then the result after typeset: Pls see the second guy, why the Matrix move "upwards" a little bit? The equal sign doesn't show up in the middle of the matrix and it looks weird. So my question:

1). Is there any way to adjust the code and make the matrix be symmetry about the equal sign?

2). Do you know any other package/better way to add text beside a matrix?

Thanks!

No need for blkarray for such a simple case, an easier option is to concatenate two arrays side-by-side. The left array can be a pmatrix to automatically get the round parens.

\documentclass[12pt]{article}
\usepackage{amsmath}
\begin{document}

$\begin{pmatrix} A & B \\ C & D \end{pmatrix} % \begin{array}{c} \text{text one}\\ \text{text two} \end{array}$

$M=\begin{pmatrix} A & B \\ C & D \end{pmatrix} % \begin{array}{c} \text{text one}\\ \text{text two} \end{array}$

\end{document} Here I use a not-often-used feature of the tabstackengine package that allows the mode of stacks to be different than that of TABstacks. So I make the defaults stacks in "text" mode and TABstacks in "math" mode. Then I can avoid the need to apply \text{} to the text.

\documentclass[12pt]{article}
\usepackage{amsmath,tabstackengine}
\setstacktabbedgap{1.5ex}
\setstackgap{L}{1.2\baselineskip}
\stackText
\TABstackMath
\begin{document}
$\parenMatrixstack{ A & B \\ C & D } \Centerstack{ text one\\ text two }$
$M= \parenMatrixstack{ A & B \\ C & D } \Centerstack{ text one\\ text two }$
\end{document} You can use the Left{text}{delimiter} feature of blkarray, if there's nothing else on the line. Or you can use a plain pmatrix followed by a tabular. Note both solutions are centred differently:

\documentclass{article}

\usepackage{amsmath}
\usepackage{blkarray}

\begin{document}

$\begin{blockarray}{\Left{ M ={} }{(}cc)l} A & B & \text{text one}\\ C & D & \text{text two} \end{blockarray}$

$M=\begin{pmatrix} A & B \\ C & D \end{pmatrix} \begin{tabular}{@{\,}l} text one\\ text two \end{tabular}$

\end{document} I would stick with the array environment, possibly enirched by multirow and bigdelim. It's a bit of a pain to mess around with spaces, but I posted an example to prove how to do it.

The details are in multirow documentation

\documentclass{article}
\usepackage{amsmath,mathtools,multirow,bigdelim}

\begin{document}
$\begin{array}{ccc@{\,}lc} \ldelim( {2}{0pt}& A&B&\rdelim){2}{0.5em}&\text{text one}\\ &C&D& &\text{text two}\\ \end{array}$
$M=\begin{array}{@{}ccc@{\,}lc} \ldelim( {2}{0pt}& A&B&\rdelim){2}{0.5em}&\text{text one}\\ &C&D& &\text{text two}\\ \end{array}$
\end{document} 