在两个节点之间画半线 tikz

Question

我有以下图表：

\documentclass[border=1mm]{standalone}
\usepackage{siunitx}
\usepackage{tikz}

\begin{document}

\begin{tikzpicture}
]
  \node (n1) at (0,0)  [draw=black,auto=left,circle,thick,fill=red!50,scale=1.3] {$\mathbf{X}_1$};
  \node (n2) at (2,2)  [draw=black,auto=left,circle,thick,fill=red!50,scale=1.3] {$\mathbf{X}_2$};
  \node (n3) at (4,4)  [draw=black,auto=left,circle,thick,fill=red!50,scale=1.3] {$\mathbf{X}_3$};  

  \node (n4) at (3,0)  [draw=black,auto=left,circle,thick,fill=red!50,scale=1.3] {$\mathbf{X}_4$};
  \node (n5) at (5,2)  [draw=black,auto=left,circle,thick,fill=red!50,scale=1.3] {$\mathbf{X}_5$};
  \node (n6) at (7,4)  [draw=black,auto=left,circle,thick,fill=red!50,scale=1.3] {$\mathbf{X}_6$};  

  \node (n7) at (6,0)  [draw=black,auto=left,circle,thick,fill=red!50,scale=1.3] {$\mathbf{X}_7$};
  \node (n8) at (8,2)  [draw=black,auto=left,circle,thick,fill=red!50,scale=1.3] {$\mathbf{X}_8$};
  \node (n9) at (10,4) [draw=black,auto=left,circle,thick,fill=red!50,scale=1.3] {$\mathbf{X}_9$}; 

  \node (n11) at (0,5)  [draw=black,auto=left,circle,thick,fill=green!50,scale=1.2] {$\mathbf{Y}_{10}$};
  \node (n22) at (2,7)  [draw=black,auto=left,circle,thick,fill=green!50,scale=1.2] {$\mathbf{Y}_{11}$};
  \node (n33) at (4,9)  [draw=black,auto=left,circle,thick,fill=green!50,scale=1.2] {$\mathbf{Y}_{12}$};

  \node (n44) at (3,5)  [draw=black,auto=left,circle,thick,fill=green!50,scale=1.2] {$\mathbf{Y}_{13}$};
  \node (n55) at (5,7)  [draw=black,auto=left,circle,thick,fill=green!50,scale=1.2] {$\mathbf{Y}_{14}$};
  \node (n66) at (7,9)  [draw=black,auto=left,circle,thick,fill=green!50,scale=1.2] {$\mathbf{Y}_{15}$}; 

  \node (n77) at (6,5)  [draw=black,auto=left,circle,thick,fill=green!50,scale=1.2] {$\mathbf{Y}_{16}$};
  \node (n88) at (8,7)  [draw=black,auto=left,circle,thick,fill=green!50,scale=1.2] {$\mathbf{Y}_{17}$};
  \node (n99) at (10,9) [draw=black,auto=left,circle,thick,fill=green!50,scale=1.2] {$\mathbf{Y}_{18}$};  

  \node (n7h) at (9,0)  [] {$ $};
  \node (n8h) at (11,2) [] {$ $};
  \node (n9h) at (13,4) [] {$ $}; 

  \node (n1l) at (-3,0) [] {$ $};
  \node (n2l) at (-1,2) [] {$ $};
  \node (n3l) at (1,4)  [] {$ $};  

  \node (n1f) at (-2,-2) [] {$ $};
  \node (n4f) at (1,-2)  [] {$ $};
  \node (n7f) at (4,-2)  [] {$ $};  

  \node (n3t) at (6,6)  [] {$ $};
  \node (n6t) at (9,6)  [] {$ $};\draw ($(n1)!1cm!(n1l)$) -- ($(n1)!3cm!(n1l)$);
  \node (n9t) at (12,6) [] {$ $};

  \foreach \from/\to in {n11/n1,n22/n2,n33/n3,n44/n4,n55/n5,n66/n6,n77/n7,n88/n8,n99/n9}[ultra thin] \draw (\from) -- (\to);        
  \foreach \from/\to in {n1/n2,n2/n3,n4/n5,n5/n6,n7/n8,n8/n9} \draw[ultra thick] (\from) -- (\to);            
  \foreach \from/\to in {n1/n4,n4/n7,n2/n5,n5/n8,n3/n6,n6/n9} \draw[ultra thick] (\from) -- (\to);    
  \foreach \from/\to in {n7/n7h,n8/n8h,n9/n9h} \draw (\from)[dashed] -- (\to);     
  \foreach \from/\to in {n1/n1l,n2/n2l,n3/n3l} \draw (\from)[dashed] -- (\to); 
  \foreach \from/\to in {n1/n1f,n4/n4f,n7/n7f} \draw (\from)[dashed] -- (\to);  
  \foreach \from/\to in {n3/n3t,n6/n6t,n9/n9t} \draw (\from)[dashed] -- (\to);   
\end{tikzpicture}

\end{document}

我想画一条半虚线，例如在节点 X_1 和 Y_{13} 之间。我该怎么做？

Answer 1

“半虚线”的另一种解释：

\documentclass[tikz,border=5]{standalone}
\usetikzlibrary{decorations.pathreplacing,calc}
\tikzset{draw half paths/.style 2 args={%
  decoration={show path construction,
    lineto code={
      \draw [#1] (\tikzinputsegmentfirst) -- 
         ($(\tikzinputsegmentfirst)!0.5!(\tikzinputsegmentlast)$);
      \draw [#2] ($(\tikzinputsegmentfirst)!0.5!(\tikzinputsegmentlast)$)
        -- (\tikzinputsegmentlast);
    }
  }, decorate
}}
\begin{document}
\begin{tikzpicture}[every node/.style={circle, draw}, >=stealth]
\foreach \i in {1,...,5}
  \node (n-\i) at (72*\i:2) {\i};

\path [draw half paths={solid}{dashed}]  (n-1) -- (n-3);
\path [draw half paths={dotted}{dashed}] (n-2) -- (n-4);
\path [draw half paths={blue, thin}{red, very thick}] (n-3) -- (n-5);
\path [draw half paths={dashed}{draw=none}] (n-4) -- (n-1);
\path [draw half paths={dotted, ->}{draw=none}] (n-5) -- (n-2);
\end{tikzpicture}
\end{document}

Answer 2

我不太确定，您为什么介意“半虚线”......如果它由两条线组成，一条实线和一条（与实线距离不远）虚线，看看这是否能解决您的问题：

\begin{scope}[on background layer]
% half dashed line
\draw (n1) -- (n13);
\draw[dashed] ($(n1)!2pt!90:(n13)$) edge ($(n13)!2pt!-90:(n1)$);
\end{scope}

此项添加可得出：

这张图片是我用 MWE 生成的，嗯，与你的非常不同......

\documentclass[border=3mm, tikz, preview]{standalone}
\usepackage{siunitx}
\usepackage{tikz}
\usetikzlibrary{calc,backgrounds,scopes}

\begin{document}
    \begin{tikzpicture}[
XYnode/.style = {circle, draw=black, thick, fill=#1!50,
                minimum size=1em, font=\Large},
                    ]
% red nodes
\foreach \x in {1,2,...,3}
\foreach \y in {1,2,...,3}
{
    \pgfmathtruncatemacro{\i}{\y + (\x-1)*3};
\node[XYnode=red] (n\i) at ({3*(\x+\y-2)-\y},2*\y-2) {$\mathbf{X}_{\i}$};
}
%green nodes
    \begin{scope}[yshift=50mm]
\foreach \x in {1,2,...,3}
\foreach \y in {1,2,...,3}
{
    \pgfmathtruncatemacro{\i}{\y + (\x-1)*3 + 9};
\node[XYnode=green] (n\i) at ({3*(\x+\y-2)-\y},2*\y-2) {$\mathbf{Y}_{\!\!\i}$};
}
    \end{scope}
% background lines 
\begin{scope}[on background layer]
% grid below red nodes
    \draw[ultra thick]  (n1) -- (n3) (n4) -- (n6) (n7) -- (n9)
                        (n1) -- (n7) (n2) -- (n8) (n3) -- (n9);
% half dashed line
\draw (n1) -- (n13);
\draw[dashed] ($(n1)!2pt!90:(n13)$) -- ($(n13)!2pt!-90:(n1)$);
\end{scope}
% links between red and green nodes
\foreach \j [count=\jj from 10] in {1,...,9}
    \draw (n\j) -- (n\jj);
% dashed lines
\foreach \k [count=\kk from 7] in {1,...,3}
    \draw[dashed] (n\k) -- + (-33mm,0mm) (n\kk) -- + (33mm,0mm);
\foreach \k [evaluate=\k as \kk using int(\k + 2)] in {1,4,...,7}
    \draw[dashed] (n\k)  -- + (-18mm,-18mm)
                  (n\kk) -- + ( 22mm, 22mm);
    \end{tikzpicture}