如何在 Latex 分数环境中正确对齐 Tikz 图片

Question

如何在Latex环境中正确对齐Tikz图片以获得以下图片？

我的试用代码无法编译，

\documentclass[preview]{standalone}
\usepackage{tikz}
\usepackage{amsmath}
\begin{document}

\begin{equation*}
    A = \frac{%
        \begin{tikzpicture}
            \draw (0,0) to[bend left] (1,0) to[bend left] (0,0);
        \end{tikzpicture}
    }{%
        \begin{tikzpicture}
            \def\L{1.0} 
            \matrix[column sep=.1cm, row sep=2mm]
            {   
                \draw (0,0) to[bend left] (\L,0) to[bend left] (0,0);
                &
                \node at (0,0) {$-$};
                &
                \draw[dashed] (0,0) -- (\L,0);
                \draw[xshift=\L cm] (0,0) to[bend left] (\L,0) to[bend left] (0,0); \\
            };
        \end{tikzpicture}
    }
\end{equation*}

\end{document}

Answer 1

通常，您可以使用选项控制垂直对齐baseline。

\documentclass{article}
\usepackage{amsmath}
\usepackage{tikz}
\begin{document}
\begin{equation*}
    A = \frac{%
        \begin{tikzpicture}[baseline={(0,-0.1)}]
            \draw (0,0) to[bend left] (1,0) to[bend left] (0,0);
        \end{tikzpicture}
    }{%
    \begin{tikzpicture}[baseline={(0,-0.1)}]
            \draw (0,0) to[bend left] (1,0) to[bend left] (0,0);
     \end{tikzpicture}
     -
    \begin{tikzpicture}[baseline={(0,-0.1)}]
            \draw (0,0) to[bend left] (1,0) to[bend left] (0,0);
            \draw[dashed](0,0) -- (-1,0);
     \end{tikzpicture}
    }
\end{equation*}

\end{document}

我不知道这些物体代表什么，所以您可能需要使用另一个基线。

请注意，您可以使用 Ti钾Z矩阵：

\documentclass{article}
\usepackage{tikz}
\usepackage{amsmath}
\begin{document}

\begin{equation*}
    A = \frac{%
        \begin{tikzpicture}[baseline]
            \draw (0,0) to[bend left] (1,0) to[bend left] (0,0);
        \end{tikzpicture}
    }{%
        \begin{tikzpicture}[baseline]
            \def\L{1.0} 
            \matrix[column sep=.1cm, row sep=2mm,ampersand replacement=\&]
            {   
                \draw (0,0) to[bend left] (\L,0) to[bend left] (0,0);
                \&
                \node at (0,0) {$-$};
                \&
                \draw[dashed] (0,0) -- (\L,0);
                \draw[xshift=\L cm] (0,0) to[bend left] (\L,0) to[bend left] (0,0); \\
            };
        \end{tikzpicture}
    }
\end{equation*}

\end{document}

Answer 2

\documentclass{article}
\usepackage{tikz}

\begin{document}
\[
A = \frac{\tikz[baseline=1pt]{\draw  (-1.5,0) to[bend left] (-0.5,0) to[bend left] (-1.5,0);}}
         {\tikz{\draw  (-1.5,0) to[bend left] (-0.5,0) to[bend left] (-1.5,0)
                       ( 0.5,0) to[bend left] ( 1.5,0) to[bend left] ( 0.5,0);
                \draw[dashed, shorten >=1mm, shorten <=1mm] (-0.5,0) -- (0.5,0);}
         }
\]
\end{document}