对齐方程、矩阵和表格

Question

我需要将此方程调整为：

我使用方程式、矩阵和表格环境重新创建了它。

\begin{equation} \hat{J}_x \leftrightarrow \frac{\hbar}{2}
\begin{pmatrix}
  \begin{tabular}{ c | c | c | c | c }
    0 & 0 & 0 & 0 &   \\ \hline
    \multirow{2}{*}{0} & 0\ 1 & \multirow{2}{*}{0} & \multirow{2}{*}{0} \\ & 1\ 0 &  &  \\ \hline
    \multirow{3}{*}{0} & \multirow{3}{*}{0} & 0\ \ $\sqrt{2}$\ \ 0 & \multirow{3}{*}{0} \\ &  & $\sqrt{2}$\ \ 0\ $\sqrt{2}$ & \\ & & 0\ \ $\sqrt{2}$\ \ 0 &  \\ \hline
    \multirow{4}{*}{0} & \multirow{4}{*}{0} & \multirow{4}{*}{0} & 0\ $\sqrt{3}$\ 0\ 0 &  \\
    & & & $\sqrt{3}$\ 0\ 2\ 0 & \\
    & & & 0\ 2\ 0\ $\sqrt{3}$ & \\
    & & & 0\ 0\ $\sqrt{3}$\ 0&  \\ \hline
    & & & & $\ddots$ \\
  \end{tabular}
  \end{pmatrix}
\end{equation}

我得到这个：

但我需要将等式的第一部分对齐到左上角。此外，表格中的对齐方式有点不对。有什么想法吗？

Answer 1

您可以用它delarray来对矩阵进行顶部对齐以及gathered对方程编号进行居中对齐。

\documentclass{article}
\usepackage{amsmath}
\usepackage{delarray}

\begin{document}

\begin{equation}
\begin{gathered}
\hat{J}_x \leftrightarrow \frac{\hbar}{2}
\begin{array}[t]({ c | c | c | c | c })
0 & 0 & 0 & 0 & \vphantom{\Big|} \\
\hline
0 & \begin{matrix} 1 & 0 \\ 0 & 1\end{matrix} & 0 &  &  \\
\hline
0 & 0 & \begin{matrix}
        0 & \sqrt{2} & 0 \\
        \sqrt{2} & 0 & \sqrt{2} \\
        0 & \sqrt{2} & 0
        \end{matrix} & 0 & \\
\hline
0 & 0 & 0 & \begin{matrix}
            0 & \sqrt{3} & 0 & 0 \\
            \sqrt{3} & 0 & 2 & 0 \\
            0 & 2 & 0 & \sqrt{3} \\
            0 & 0 & \sqrt{3} & 0
            \end{matrix} & \\
\hline
    & & & & \ddots
\end{array}
\end{gathered}
\end{equation}

\end{document}

嵌套矩阵比滥用容易得多\multirow。

消除gathered收益

另一方面，我认为这并不是很清楚。

如果您改变主意：

\documentclass{article}
\usepackage{amsmath}

\begin{document}

\begin{equation}
\hat{J}_x \leftrightarrow \frac{\hbar}{2}
\left(\begin{array}{ @{} c | c | c | c | c @{} }
0 & 0 & 0 & 0 & \vphantom{\Big|} \\
\hline
0 & \begin{matrix} 1 & 0 \\ 0 & 1\end{matrix} & 0 &  &  \\
\hline
0 & 0 & \begin{matrix}
        0 & \sqrt{2} & 0 \\
        \sqrt{2} & 0 & \sqrt{2} \\
        0 & \sqrt{2} & 0
        \end{matrix} & 0 & \\
\hline
0 & 0 & 0 & \begin{matrix}
            0 & \sqrt{3} & 0 & 0 \\
            \sqrt{3} & 0 & 2 & 0 \\
            0 & 2 & 0 & \sqrt{3} \\
            0 & 0 & \sqrt{3} & 0
            \end{matrix} & \\
\hline
    & & & & \ddots
\end{array}\right)
\end{equation}

\end{document}

您可以通过设置来获得更开放的外观\extrarowheight。我只会显示它添加到最后的代码，该方法适用于其他两个示例。

\documentclass{article}
\usepackage{amsmath}
\usepackage{array}

\begin{document}

\begin{equation}
\setlength{\extrarowheight}{2pt}
\hat{J}_x \leftrightarrow \frac{\hbar}{2}
\left(\begin{array}{ @{} c | c | c | c | c @{} }
0 & 0 & 0 & 0 & \vphantom{\Big|} \\
\hline
0 & \begin{matrix} 1 & 0 \\ 0 & 1\end{matrix} & 0 &  &  \\
\hline
0 & 0 & \begin{matrix}
        0 & \sqrt{2} & 0 \\
        \sqrt{2} & 0 & \sqrt{2} \\
        0 & \sqrt{2} & 0
        \end{matrix} & 0 & \\
\hline
0 & 0 & 0 & \begin{matrix}
            0 & \sqrt{3} & 0 & 0 \\
            \sqrt{3} & 0 & 2 & 0 \\
            0 & 2 & 0 & \sqrt{3} \\
            0 & 0 & \sqrt{3} & 0
            \end{matrix} & \\
\hline
    & & & & \ddots
\end{array}\right)
\end{equation}

\end{document}

Answer 2

您可以使用\raisebox{-\height}降低框来将其移动到基线以下并\raisebox{\dimexpr-\height+\baselineskip\relax}使其处于正确的高度：

\documentclass[]{article}

\usepackage[]{amsmath}
\usepackage{multirow}

\begin{document}
\begin{equation} \hat{J}_x \leftrightarrow \frac{\hbar}{2}
  \raisebox{\dimexpr-\height+\baselineskip\relax}
    {%
      $\begin{pmatrix}
      \begin{array}{ c | c | c | c | c }
        0 & 0 & 0 & 0 &   \\ \hline
        \multirow{2}{*}{0} & 0\ 1 & \multirow{2}{*}{0} & \multirow{2}{*}{0} \\ & 1\ 0 &  &  \\ \hline
        \multirow{3}{*}{0} & \multirow{3}{*}{0} & 0\ \ \sqrt{2}\ \ 0 & \multirow{3}{*}{0} \\ &  & \sqrt{2}\ \ 0\ \sqrt{2} & \\ & & 0\ \ \sqrt{2}\ \ 0 &  \\ \hline
        \multirow{4}{*}{0} & \multirow{4}{*}{0} & \multirow{4}{*}{0} & 0\ \sqrt{3}\ 0\ 0 &  \\
        & & & \sqrt{3}\ 0\ 2\ 0 & \\ 
        & & & 0\ 2\ 0\ \sqrt{3} & \\
        & & & 0\ 0\ \sqrt{3}\ 0&  \\ \hline
        & & & & \ddots \\ 
      \end{array}
      \end{pmatrix}$%
    }
\end{equation}
\end{document}

Answer 3

如果您希望 eq 号与顶部对齐，则只需将其放在pmatrix中即可\belowbaseline[-\ht\strutbox]{...}。

\documentclass{article}
\usepackage{amsmath,multirow,stackengine}
\begin{document}
\begin{equation} \hat{J}_x \leftrightarrow \frac{\hbar}{2}
\belowbaseline[-\ht\strutbox]{$\begin{pmatrix}
  \begin{tabular}{ c | c | c | c | c }
    0 & 0 & 0 & 0 &   \\ \hline
    \multirow{2}{*}{0} & 0\ 1 & \multirow{2}{*}{0} & \multirow{2}{*}{0} \\ & 1\ 0 &  &  \\ \hline
    \multirow{3}{*}{0} & \multirow{3}{*}{0} & 0\ \ $\sqrt{2}$\ \ 0 & \multirow{3}{*}{0} \\ &  & $\sqrt{2}$\ \ 0\ $\sqrt{2}$ & \\ & & 0\ \ $\sqrt{2}$\ \ 0 &  \\ \hline
    \multirow{4}{*}{0} & \multirow{4}{*}{0} & \multirow{4}{*}{0} & 0\ $\sqrt{3}$\ 0\ 0 &  \\
    & & & $\sqrt{3}$\ 0\ 2\ 0 & \\ 
    & & & 0\ 2\ 0\ $\sqrt{3}$ & \\
    & & & 0\ 0\ $\sqrt{3}$\ 0&  \\ \hline
    & & & & $\ddots$ \\ 
  \end{tabular}
  \end{pmatrix}$}
\end{equation}
\end{document}

如果你想让数字居中，那么只需将整个数字包裹在\vcenter{\hbox{$\displaystyle...$}}

\documentclass{article}
\usepackage{amsmath,multirow,stackengine}
\begin{document}
\begin{equation} \vcenter{\hbox{$\displaystyle\hat{J}_x \leftrightarrow \frac{\hbar}{2}
\belowbaseline[-\ht\strutbox]{$\begin{pmatrix}
  \begin{tabular}{ c | c | c | c | c }
    0 & 0 & 0 & 0 &   \\ \hline
    \multirow{2}{*}{0} & 0\ 1 & \multirow{2}{*}{0} & \multirow{2}{*}{0} \\ & 1\ 0 &  &  \\ \hline
    \multirow{3}{*}{0} & \multirow{3}{*}{0} & 0\ \ $\sqrt{2}$\ \ 0 & \multirow{3}{*}{0} \\ &  & $\sqrt{2}$\ \ 0\ $\sqrt{2}$ & \\ & & 0\ \ $\sqrt{2}$\ \ 0 &  \\ \hline
    \multirow{4}{*}{0} & \multirow{4}{*}{0} & \multirow{4}{*}{0} & 0\ $\sqrt{3}$\ 0\ 0 &  \\
    & & & $\sqrt{3}$\ 0\ 2\ 0 & \\ 
    & & & 0\ 2\ 0\ $\sqrt{3}$ & \\
    & & & 0\ 0\ $\sqrt{3}$\ 0&  \\ \hline
    & & & & $\ddots$ \\ 
  \end{tabular}
  \end{pmatrix}$}$}}
\end{equation}
\end{document}