How to enlarge zeros in the tkz-tab package?

Question

In this code how can I enlarge the zeros? The documentation is in German and I don't know the German language.

\documentclass{article}
\usepackage{tkz-tab}

\begin{document}
\begin{tikzpicture}
\tkzTabInit[espcl=1.5]
{$x$ / 1 ,$f(x)$ /1 }%
{$v_1$ , $v_2$ , $v_3$ }%
\tkzTabLine{ z, , z , ,z }
\end{tikzpicture}
\end{document}

Answer 1

You can for example patch the command \tkzTabLine using xpatch package, and change the line of code

\node at (Z\thetkz@cnt@impair\thetkz@cnt@lg){$0$};

With

\node[font=\Large] at (Z\thetkz@cnt@impair\thetkz@cnt@lg){$0$}; 

To change the size of font inside node containing zeros

Code

\documentclass{article}
\usepackage{xpatch}
\usepackage{tkz-tab}

\makeatletter
\xpatchcmd{\tkzTabLine}
{\node at (Z\thetkz@cnt@impair\thetkz@cnt@lg){$0$};} % search
{\node[font=\Large] at (Z\thetkz@cnt@impair\thetkz@cnt@lg){$0$};} % replace
{}{}
\makeatother

\begin{document}
\begin{tikzpicture}
\tkzTabInit[espcl=1.5]
{$x$ / 1 ,$f(x)$ /1 }%
{$v_1$ , $v_2$ , $v_3$ }%
\tkzTabLine{z , , z , ,z }

\end{tikzpicture}
\end{document}

Result