[Tex/LaTex] Typesetting on block matrix is ugly

arraysmath-modematrices

I have a large n x n matrix I'm trying to typeset. My current code is as follows:

$\left(\begin{array}{c|ccc}
1 & c_2 & \cdots & c_n \\
\hline
0  & \multicolumn{3}{c}{\multirow{3}{*}{\Huge{$A$}}} \\
\vdots & & &\\
0 & & & 
\end{array}\right)$

The output is currently terrible in a number of ways. First, the large block A matrix (which is supposed to be an (n-1) x (n-1) submatrix) is not centered properly. Second, the vertical dots on the left hand side are not properly vertically centered. Third, it is just visually unappealing in a way that I can't quite put my finger on.

Does anyone have any suggestions on how to typeset this in a better manner?

Best Answer

Another option would be to use a two-column array:

\documentclass{article}

\begin{document}

\[
\left(
\begin{array}{c|c}
  1 & c_2 \cdots c_n \\ \hline
  0 & \raisebox{-15pt}{{\huge\mbox{{$A$}}}} \\[-4ex]
  \vdots & \\[-0.5ex]
  0 &
\end{array}
\right)
\]

\end{document}

enter image description here

Related Solutions

[Tex/LaTex] Compact block matrix

use the default tabcolsep and increase the array stretch:

\documentclass{article}

\usepackage[fleqn]{amsmath}
\usepackage{blkarray}
\usepackage{multirow}
\usepackage{mathtools}
\usepackage{graphicx}
\newcommand{\rdots}{\hspace{.2ex}\raisebox{1ex}{\rotatebox{-12}{$\ddots$}}}

\begin{document}

\begin{equation}\def\arraystretch{1.5}
    \begin{blockarray}{(ccc|ccc)l}
        1&&0&\BAmulticolumn{3}{c}{\multirow{3}{*}{\huge$0$}}&\multirow{3}{*}{$\dim F\;\text{vertical}$}\\&\rdots&&&&&\\0&&1&&&&\\
        \cline{1-6}
        \BAmulticolumn{3}{c|}{\multirow{3}{*}{\huge$0$}}&\tfrac{1}{t}&&0&\multirow{3}{*}{$\dim Z\;\text{horizontal}$}\\&&&&\rdots&&\\&&&0&&\frac{1}{t}&\\
    \end{blockarray}
\end{equation}

\end{document}

enter image description here

Using a small matrix makes also sense:

\begin{equation}
 \left(
    \begin{array}{r@{}c|c@{}l}
  &    \begin{smallmatrix}
        1 & & 0 \\
          &\ddots&\\
        0 & & 1\rule[-1ex]{0pt}{2ex}
      \end{smallmatrix} & \mbox{\huge0} & \rlap{\kern5mm$\dim F$ vertical}\\\hline
  &    \mbox{\huge0} &  
       \begin{smallmatrix}\rule{0pt}{2ex}
        \frac1t & & 0 \\
          &\ddots&\\
        0 & & \frac1t
      \end{smallmatrix}    &  \rlap{\kern5mm$\dim Z$ horizontal}
    \end{array} 
\right)
\end{equation}

enter image description here

[Tex/LaTex] Matrix derivation

amsmath has some fancy code for double accents and having \hat inside \dot triggers bits of that in unintended ways. Easiest is to pre-set the inner expression in a box.

enter image description here

\documentclass{report}
 \usepackage[utf8x]{inputenc}
 \usepackage{amsmath,amsfonts,mathrsfs,amssymb,dsfont}
\begin{document}

 \begin{align}
 \sbox0{$\begin{pmatrix}\hat{x} \\ \hat{y} \end{pmatrix}$}\dot{\usebox{0}}
 \end{align}
\end{document}

Best Answer

Related Solutions

[Tex/LaTex] Compact block matrix

[Tex/LaTex] Matrix derivation

Related Question