LaTeX 小技巧(4) - 分類圖 (amsmath 套件, package: cases)

用法:

%==== preamble 區

\usepackage{amsmath}

%==== 正文

\begin{cases}
    class1 \\
    class2 \\
    class3
\end{cases}

如 $\begin{cases}class1 \\class2 \\class3\end{cases}$
cases環境可以 nested 也不會自動換行

複雜一點的例子是 :

\text{Groups} \begin{cases}

    \text{Cyclic Subgroups} \rightarrow \fbox{\text{Basis Theorem for Finite Abelian Groups}} \\

    \text{Normal Subgroups} \begin{cases}

        \text{Composition Series} \rightarrow \fbox{\text{Jordan-Holder Theorem}}\\

        \text{Simple Groups} \rightarrow \frame{

            \begin{tabular}[t]{c}Classification Theorem of Finite Simple Groups \\ \end{tabular} }

        \end{cases}\\

    \text{Commutator Subgroups} \rightarrow \text{Sovable Groups} \rightarrow \fbox{\text{Galois Theory}} \rightarrow \cdots\\

    \text{Group Actioin} \begin{cases}

        \fbox{\text{Group Representation Thoery}} \rightarrow \cdots\\

        \text{Class Equation} \rightarrow \fbox{\text{Polya Enumeration Theorem}}

        \end{cases}\\

    \text{Sylow Subgroups} \rightarrow \fbox{\text{Sylow Theorem}}

\end{cases}

得

$\text{Groups}\begin{cases} \text{Cyclic Subgroups}\rightarrow\fbox{\text{Basis Theorem for Finite Abelian Groups}}\\ \text{Normal Subgroups} \begin{cases} \text{Composition Series} \rightarrow \text{Jordan-Holder Theorem}\\ \text{Simple Groups} \rightarrow \frame{\begin{tabular}[t]{c}Classification Theorem of Finite Simple Groups \\ \end{tabular}} \end{cases}\\ \text{Commutator Subgroups} \rightarrow \text{Sovable Groups} \rightarrow \fbox{\text{Galois Theory}} \rightarrow \cdots\\ \text{Group Actioin} \begin{cases}\fbox{\text{Group Representation Theory}} \rightarrow \cdots \\ \text{Class Equation} \rightarrow \fbox{\text{Polya Enumeration Theorem}} \end{cases}\\ \text{Sylow Subgroups} \rightarrow \fbox{\text{Sylow Theorem}}\end{cases}$