如何用 tkz-tab 在此图片上绘制 \rightarrow？

Question

我尝试绘制变体表。我尝试

\documentclass[12pt]{article}
\usepackage{tkz-tab}
\tikzset{t style/.style = {style = densely dashed}}
\begin{document}
\begin{center}
\begin{tikzpicture}
\tkzTabInit[espcl=3]%
{$x$/1,$f'(x)$/1, $f(x)$/3}{$-\infty$,$1$,$+\infty$}%
\tkzTabLine{, +,z,+,}
\tkzTabVar{-/ $-\infty$, R/ , +/$+\infty$ }
\tkzTabImaFrom{1}{3}{N21}{$3$}
\end{tikzpicture}
\end{center}
\end{document}

我有

像这个图这样要怎么画呢？

Answer 1

这里有一个解决方案\tkzTabImaFrom

\documentclass[12pt]{article}
\usepackage{tkz-tab}
\tikzset{t style/.style = {style = densely dashed}}
\begin{document}
\begin{center}
\begin{tikzpicture}
\tkzTabInit[espcl=3]%
{$x$/1,$f'(x)$/1, $f(x)$/3}{$-\infty$,$1$,$+\infty$}%
\tkzTabLine{, +,z,+,}
\tkzTabVar{-/ $-\infty$, R/ , +/$+\infty$ }
\path (FR12) -- (FL32)node[midway,fill=white](M){$3$};
\draw[arrow style,shorten >=-2pt](FR12)--(M);
\end{tikzpicture}
\end{center}
\end{document}

Answer 2

另一个解决方案：

\documentclass[12pt]{article}
\usepackage{tkz-tab}
\tikzset{t style/.style = {style = densely dashed}}
\begin{document}
\begin{center}
\begin{tikzpicture}
\tkzTabInit[espcl=3]%
{$x$/1,$f'(x)$/1, $f(x)$/3}{$-\infty$,$1$,$+\infty$}%
\tkzTabLine{, +,z,+,}
\node[above=6pt] (n1) at (N13) {-\infty};
\node[below=6pt] (n2) at (N32) {+\infty};
\path (n1) -- (n2) node[midway,fill=white](m){$3$};
\draw[arrow style,shorten >=-2pt](n1) to (m);
\draw[arrow style,shorten >=-2pt](m) to (n2);
\end{tikzpicture}
\end{center}
\end{document}