[Tex/LaTex] How to make a square grid in latex

diagramsgraphs

I want to make the following square grid in latex. Can anyone please help me on this ? .

\documentclass[a4paper]{article}
\usepackage{tikz}
\begin{document}
\begin{tikzpicture}[scale=0.4, vertices/.style={draw, fill=black, circle, inner sep=0.5pt}]
\node[vertices, label=left:{$a_{13}$}] (a) at (1,1) {};
\node[vertices, label=below:{$a_{14}$}] (b) at (5,1) {};
\node[vertices,label=below:{$a_{15}$}] (c) at (18,1) {};
\node[vertices,label=right:{$a_{13}$}] (d) at (22,1) {};
\node[vertices,label=left:{$a_{11}$}] (e) at (1,5) {}; 
\node[vertices, label=right:{$a_{12}$}] (f) at (5,5) {};
\node[vertices, label=left:{$a_{16}$}] (g) at (18,5) {};
\node[vertices, label=right:{$a_{11}$}] (h) at (22,5) {};
\node[vertices, label=left:{$a_{8}$}] (i) at (1,13) {};
\node[vertices, label=right:{$a_{10}$}] (j) at (5,13) {};
\node[vertices, label=left:{$a_{7}$}] (k) at (1,17) {};
\node[vertices, label=right:{$a_{9}$}] (l) at (5,17) {};
\node[vertices, label=left:{$a_{2}$}] (m) at (1,21) {};
\node[vertices, label=right:{$a_{3}$}] (n) at (5,21) {};
\node[vertices, label=left:{$a_{1}$}] (o) at (1,25) {};
\node[vertices, label=above:{$a_{5}$}] (p) at (5,25) {};
\node[vertices, label=above:{$a_{6}$}] (q) at (9,25) {};
\node[vertices, label=right:{$a_{4}$}] (r) at (9,21) {};
\node[vertices, label=above:{$a_{20}$}] (s) at (18,25) {};
\node[vertices, label=right:{$a_{1}$}] (t) at (22,25) {};
\node[vertices, label=left:{$a_{19}$}] (u) at (18,21) {};
\node[vertices, label=right:{$a_{2}$}] (v) at (22,21) {};
\node[vertices, label=left:{$a_{18}$}] (w) at (18,17) {};
\node[vertices, label=right:{$a_{7}$}] (x) at (22,17) {};
\node[vertices, label=left:{$a_{17}$}] (y) at (18,13) {};
\node[vertices, label=right:{$a_{8}$}] (z) at (22,13) {};
\foreach \to/\from in
{a/b,a/e,e/f,b/f,c/d,c/g,g/h,h/d,k/i, k/l, l/j, i/j, k/j, o/m, o/p, o/n, m/n, n/p, m/k, m/l,     l/n, p/q, p/r, q/r, r/n, s/u, s/t, u/v, t/v, s/v, u/w,v/x, w/x, u/x, w/y, x/z, y/z, z/w, e/b, g/d} \draw [-] (\to)--(\from);
\foreach \to/\from in
{b/c,f/g, e/i,j/f, q/s, r/u, l/w, y/g, z/h, j/y} \draw [dashed]     (\to)--     (\from);
\end{tikzpicture}
\end{document}

Best Answer

There might be easier ways, but I think a Tikz matrix is a good approach.

Output

enter image description here

Code

\documentclass[tikz,margin=10pt]{standalone}

\usetikzlibrary{matrix}

\tikzset{
    basic/.style={
        rectangle,
        minimum size=1.8cm,
        text depth=0.5ex,
        text height=2ex,
        inner sep=0pt,
        outer sep=0pt,
    },
    table nodes/.style 2 args={
        draw=black,
        append after command={
            \pgfextra{\draw (\tikzlastnode.north west) -- (\tikzlastnode.south east) 
                node[midway, anchor=north east, minimum size=7mm] {#1}
                node[midway, anchor=south west, minimum size=7mm] {#2};
            }
        }
    },      
    table/.style={
        matrix of nodes,
        row sep=-\pgflinewidth,
        column sep=-\pgflinewidth,
        nodes={   
            basic        
        },
        execute at empty cell={\node{};}
    }
}

\newcommand\dcell[2]{%
    |[table nodes={#1}{#2}]|
}

\newcommand\link[3]{%
    \def\switchrow{row}
    \def\switchcol{col}
    \def\argi{#1}
    \ifx\argi\switchrow
        \draw[gray, dashed] (#2.south east) -- (#3.south west);
        \draw[gray, dashed] (#2.north east) -- (#3.north west);
    \else\ifx\argi\switchcol
        \draw[gray, dashed] (#2.south east) -- (#3.north east);
        \draw[gray, dashed] (#2.south west) -- (#3.north west); 
    \fi
    \fi
}

\begin{document}
\begin{tikzpicture}

\matrix (m) [table]
{
    \dcell{$A_1$}{$A_2$} & \dcell{$B_1$}{$B_2$} & & & \dcell{$C_1$}{$C_2$} \\
    \dcell{$C_3$}{$C_4$} &   & & & \dcell{$C_9$}{$C_10$} \\
    \dcell{$C_5$}{$C_6$} &   & & & \dcell{}{} \\
                        &   & & &  \\
                        &   & & &  \\
    \dcell{$C_7$}{$C_8$} &   & & & \dcell{}{} \\
};

\link{row}{m-1-2}{m-1-5}
\link{row}{m-3-1}{m-3-5}
\link{row}{m-6-1}{m-6-5}

\link{col}{m-3-1}{m-6-1}
\link{col}{m-3-5}{m-6-5}

\end{tikzpicture}
\end{document}

Related Solutions

[Tex/LaTex] Simple directed hypergraphs in TikZ

A second attempt, this time making some assumptions on the layout. I assume you want the hyper-edge to always be aligned to the "lonely" node of the triplets (e.g. c in ({a,b},{c}) and ({c},{a,b}) ).

Since you seem to need fine control on the positioning of the nodes I suggest the following: first you place named nodes with manual positioning (using whichever method you prefer, from absolute coordinates to relative positioning); then you specify the hyperedges and the corresponding arcs get created. Here's a macro that can help you with the second step:

\newcommand{\hyperedge}[4][180]{
     \draw (#2.#1) ++(#1:.5)  edge (#2) edge (#3) edge (#4);
}

It takes 4 arguments (first optional): \hyperedge[angle]{c}{a}{b} draws the edges assuming that c is the lonely node and requires you to specify the angle at which the hyperedge should stick out of it.

The definition of the macro works by moving to the right/left border of the lonely node (this is accomplished by (#2.#1) which moves to the border of the node #2 at angle #1), then move right/left by .5 which is the coordinate of the "centre" of the edge; then this "centre" is connected with the nodes using the edge action.

Here's your second example using tikz and my macro:

\documentclass{standalone}
\usepackage{tikz}

\newcommand{\hyperedge}[4][180]{
     \draw (#2.#1) ++(#1:.5)  edge (#2) edge (#3) edge (#4);    
}

\begin{document}
\begin{tikzpicture}[
    y=.7cm, x=1cm,
    every edge/.append style={thick}
]

\node (a) at (-1,1) {a};
\node (b) at (-1,-1) {b};
\node (c) at (0,0) {c};
\node (d) at (1,1) {d};
\node (e) at (1,-1) {e};
\node (g) at (2,-2) {g};

\hyperedge{c}{b}{a}
\hyperedge[0]{c}{d}{e}
\hyperedge{g}{b}{e}


\end{tikzpicture}

\end{document}

Which is rather readable and easy to extend.

You can elaborate on this by using other means to specify the angle (other derived macros) or enriching it with custom styles.

Another option for the placement of the "centre" of the hyperedge is barycentric coordinates:

\newcommand{\hyperedge}[3]{
    \draw (barycentric cs:#1=1,#2=1,#3=1) edge (#1) edge (#2) edge (#3);
}

Note that this does not require the angle argument.

[Tex/LaTex] Drawing rectilinear curves in Tikz, aka an Etch-a-Sketch drawing

\draw (20,12) -- ++(2,0) -- ++(0,2) -- ++(-3,0) -- ++(45:3);

Use ++ before each new incremental coordinate to make it relative to the last one and put the pencil there.

Here's a complete example:

\documentclass{article}
\usepackage{tikz}
\begin{document}
\tikz\draw (20,12) -- ++(2,0) -- ++(0,2) -- ++(-3,0) -- ++(30:3) {[rounded corners=10pt]-- ++(5,0) -- ++(0,-6)} -- ++(-7,0) -- cycle;
\end{document}

Of course, combining this with the -| or |- path operators can simplify the code even further; the following two pieces of code produce the same result:

\tikz\draw (20,12) -- ++(2,0) -- ++(0,2) -- ++(3,0) -- ++(0,1) -- ++(1,0) -- ++(0,-3) -- ++(2,0);\par\bigskip

and

\tikz\draw (20,12) -| ++(2,2) -| ++(3,1) -- ++(1,0) |- ++(2,-3);

I don't think that defining commands in this case adds anything; in fact, I think it reduces the functionality of the existing syntax (which is already simple). The example demonstrates that you can use, for example, polar coordinates and modify (up to TikZ limitations) the path attributes midways; even if the current question doesn't require this, it's a good thing to have the possibility to do those kind of modification if they are required.