Graphics, Figures & Tables ⇒ Draw Circle around Entries inside a Matrix

[radarnasty]

I am trying to figure out how to draw a circle around single entries in a matrix. I am currently using the \begin{smallmatrix} command to create my matrices. Any help would be appreciated.

[5gon12eder]

This is a quick and dirty approach but it works:

Code: Select all

\documentclass{article}
\usepackage[T1]{fontenc}
\usepackage{amsmath}

\begin{document}
  The element $b$ in matrix $M$ is circled.
  
  \begin{equation*}
    M = 
    \left(
    \begin{array}{ccc}
      a &\text{\textcircled{$b$}} &c\\
      d &e &f\\
      g &h &i
    \end{array}
    \right)
  \end{equation*}
\end{document}

For a comprehensive discussion about circling stuff see
http://tex.stackexchange.com/questions/ ... ed-numbers

Best