我正在尝试使箭头标签看起来像是在数学模式下编写的。这就是我所拥有的：
这就是我要的
，
我尝试使用不同的字体，但没有成功。这是我的代码：
\begin{tikzpicture}[node distance=2cm,inner sep=2pt,minimum size=0.5mm, bend angle=45]
\tikzstyle{place} = [ circle,draw=black,fill=black,thick ]
\tikzstyle{surd} = [circle]
\tikzstyle{pre} = [ <-,shorten <=2pt,shorten >=2pt, >=stealth', semithick]
\tikzstyle{every node} = [font=\normalsize\itshape]
\node[place] (first) {};
\node[place] (second) [right=of first] {}
edge [pre,bend right] node [above] {$a$} (first)
edge [pre,bend left] node [below] {$b$} (first);
\node[place] (third) [right=of second] {}
edge [pre] node [above] {$c$} (second);
\node[surd] (surd) [right=of third] {\Large$\surd$}
edge [pre] node [above] {$d$} (third);
\end{tikzpicture}
答案1
对于 Beamer 类，你可能需要使用：
\usefonttheme[onlymath]{serif}
只用衬线字体显示数学。如果不想每次$进入数学模式时都输入，可以创建一个样式：
\tikzset{math mode/.style={%
execute at begin node=$,%
execute at end node=$,%
}
}
然后，通过对所有节点进行分组scope：
\begin{scope}[every node/.style={math mode}]
...
\end{scope}
该样式将被“本地”应用。
样式活动的示例math mode：
\documentclass{beamer}
\usepackage{lmodern}
\usepackage{tikz}
\usetikzlibrary{arrows,positioning}
\usefonttheme[onlymath]{serif}
\begin{document}
\begin{frame}{title}
Some text in sans serif font. Math, like:
\begin{equation}
x+y=100
\end{equation}
is rendered in serif font.
\begin{center}
\begin{tikzpicture}[node distance=2cm,inner sep=2pt,minimum size=0.5mm, bend angle=45]
\tikzset{place/.style={circle,draw=black,fill=black,thick}}
\tikzset{surd/.style={circle}}
\tikzset{pre/.style={ <-,shorten <=2pt,shorten >=2pt, >=stealth', semithick}}
% to avoid using every time dollars for math mode
\tikzset{math mode/.style={%
execute at begin node=$,%
execute at end node=$,%
}
}
\node[place] (first) {};
% using a scope to not apply the new math mode definition to all nodes
% as it might not be the desired behaviour
\begin{scope}[every node/.style={math mode}]
\node[place] (second) [right=of first] {}
edge [pre,bend right] node [above] {a} (first)
edge [pre,bend left] node [below] {b} (first);
\node[place] (third) [right=of second] {}
edge [pre] node [above] {c} (second);
\node[surd] (surd) [right=of third] {\Large\surd}
edge [pre] node [above] {d} (third);
\end{scope}
\end{tikzpicture}
\end{center}
\end{frame}
\end{document}
没有样式的完整示例math mode：
\documentclass{beamer}
\usepackage{lmodern}
\usepackage{tikz}
\usetikzlibrary{arrows,positioning}
\usefonttheme[onlymath]{serif}
\begin{document}
\begin{frame}{title}
Some text in sans serif font. Math, like:
\begin{equation}
x+y=100
\end{equation}
is rendered in serif font.
\begin{center}
\begin{tikzpicture}[node distance=2cm,inner sep=2pt,minimum size=0.5mm, bend angle=45]
\tikzset{place/.style={circle,draw=black,fill=black,thick}}
\tikzset{surd/.style={circle}}
\tikzset{pre/.style={ <-,shorten <=2pt,shorten >=2pt, >=stealth', semithick}}
%\tikzset{every node/.append style={font=\normalsize\itshape}} %useless in this case
\node[place] (first) {};
\node[place] (second) [right=of first] {}
edge [pre,bend right] node [above] {$a$} (first)
edge [pre,bend left] node [below] {$b$} (first);
\node[place] (third) [right=of second] {}
edge [pre] node [above] {$c$} (second);
\node[surd] (surd) [right=of third] {\Large$\surd$}
edge [pre] node [above] {$d$} (third);
\end{tikzpicture}
\end{center}
\end{frame}
\end{document}
结果：
