Tikz：在 \draw 中使用已定义的 \node 标签

Question

我正在使用 tikz 绘制数学结构。我已经在代码中标记了所有节点，我想将它们用作 \draw 命令中的参数，但我一直收到此错误“！缺少 \endcsname 插入。”下面是一个最低限度的工作示例。请帮助我。

\documentclass[12pt,a4paper]{article}
\usepackage{tikz}
\begin{document}
\begin{tikzpicture}
Putting node and clipping them to their respective positions
\foreach \x in {2,3,4,...,14}
    \foreach \y in {2,3,4}
    {
        \node [circle,draw=white,fill=white,inner sep=0pt,minimum size=1.8mm] (u\x\y) at (\x,\y)  {};
    }
%Drawing arrows
\foreach \x in {3,5,...,11}
    {
    \v = \x + 1;
    \draw[->>] (u\x3) -- (u\v2) ;
    }
\end{tikzpicture}
\end{document}

Answer 1

这是没有额外变量的另一种选择：

\documentclass[12pt,a4paper]{article}
\usepackage{tikz}
\begin{document}
\begin{tikzpicture}
%Putting node and clipping them to their respective positions
\foreach \x in {2,3,4,...,14}
    \foreach \y in {2,3,4}
    {
        \node [circle,draw=white,fill=white,inner sep=0pt,minimum size=1.8mm] (u\x\y) at (\x,\y)  {};
    }
%Drawing arrows
\foreach \x  in {3,5,...,11}
    {
      \draw[->>] (u\x3) -- (u\number\numexpr\x+1\relax2) ;
    }
\end{tikzpicture}
\end{document}

Answer 2

\documentclass[12pt,a4paper]{article}
\usepackage{tikz}
\begin{document}
\begin{tikzpicture}
%Putting node and clipping them to their respective positions
\foreach \x in {2,3,4,...,14}
    \foreach \y in {2,3,4}
    {
        \node [circle,draw=white,fill=white,inner sep=0pt,minimum size=1.8mm] (u\x\y) at (\x,\y)  {};
    }
%Drawing arrows
\foreach \x in {3,5,...,11}
    {
      \pgfmathparse{\x+1}
      \pgfmathtruncatemacro{\v}{\pgfmathresult}
      \draw[->>] (u\x3) -- (u\v2) ;
    }
\end{tikzpicture}
\end{document}