View source for Graphics and media/Drawing graphs and diagrams/TikZ

< [[Input and compilation/Modules|Modules]] | [[Graphics and media]] >                                                                                          

[http://pgf.sourceforge.net/ TikZ/pgf] is a portable graphics package developed for LaTeX,
also supporting ConTeXt. It is a possible alternative to [[Graphics and media/Tutorials/Graphical programming with MetaPost and MetaFun|Graphical programming with MetaPost and MetaFun]].      

TikZ is included as a (third party) module for ConTeXt.

== Example ==

From the TikZ/pgf [http://dl.contextgarden.net/modules/t-tikz/doc/generic/pgf/pgfmanual.pdf manual].

<texcode>
\setupcolors[state=start]
\definecolor[darkgreen][g=.5]
\usemodule[tikz]         

\starttext

\starttikzpicture[      scale=3,line cap=round
                        axes/.style=,         
                        important line/.style={very thick},
                        information text/.style={rounded corners,fill=red!10,inner sep=1ex} ]

        \draw[help lines,step=0.5cm] (-1.4,-1.4) grid (1.4,1.4);
        \draw (0,0) circle (1cm);                               
                \draw[->] (-1.5,0) -- (1.5,0) node[right] {$x$} coordinate(x axis);
                \draw[->] (0,-1.5) -- (0,1.5) node[above] {$y$} coordinate(y axis);
                \foreach \x/\xtext in {-1, -.5/-\frac{1}{2}, 1}                    
                        \draw[xshift=\x cm] (0pt,1pt) -- (0pt,-1pt)                
                                node[below,fill=white] {$\xtext$};
                \foreach \y/\ytext in {-1, -.5/-\frac{1}{2}, .5/\frac{1}{2}, 1}
                        \draw[yshift=\y cm] (1pt,0pt) -- (-1pt,0pt)
                                node[left,fill=white] {$\ytext$};
        \filldraw[fill=green!20,draw=green!50!black] (0,0) -- (3mm,0pt) arc(0:30:3mm);
        \draw (15:2mm) node[green!50!black] {$\alpha$};
        \draw[important line,red]
                (30:1cm) -- node[left=1pt,fill=white] {$\sin \alpha$} (30:1cm |- x axis);
        \draw[important line,blue]
                (30:1cm |- x axis) -- node[below=2pt,fill=white] {$\cos \alpha$} (0,0);
        \draw[important line,orange!80!black] (1,0) -- node[right=1pt,fill=white] {
                $\displaystyle \tan \alpha \black =
                \frac{{\red \sin \alpha}}{\blue \cos \alpha}$}
                (intersection of 0,0--30:1cm and 1,0--1,1) coordinate (t);
        \draw (0,0) -- (t);
        \draw[xshift=1.85cm]
                node[right,text width=6cm,information text]
                {
                        The {\darkgreen angle $\alpha$} is $30^\circ$ in the
                        example ($\pi/6$ in radians). The {\red sine of
                        $\alpha$}, which is the height of the red line, is
                        \startformula
                        {\red \sin \alpha} = 1/2.
                        \stopformula
                        By the Theorem of Pythagoras ...
                };
\stoptikzpicture

\stoptext
</texcode>

[[Image:TikZ_example.png]]

== Placing TikZ graphics ==

You should wrap TikZ graphics inside \hbox when placing them, for example:

<texcode>

\placefigure[here][fig:myfig]{My figure.}{\hbox{\starttikzpicture
	\draw (0, 0) circle (3cm);
\stoptikzpicture}}

</texcode>

Otherwise, positioning will not work (figure will not be centered). See [http://www.ntg.nl/pipermail/ntg-context/2007/023177.html this post] by Aditya Mahajan for explanation.

== Example for commutative diagrams ==

Hans Åberg wrote to the mailing list on 2016-10-06:

There is a tikz-cd package at CTAN: https://www.ctan.org/tex-archive/graphics/pgf/contrib/tikz-cd?lang=en

In order to use it, download the the file <code>tikzlibrarycd.code.tex</code> and put it in <code>CONTEXT_HOME/tex/texmf-modules/tex/generic/pgf/libraries/</code>. Then run
<pre>
mtxrun --generate
context --make
</pre>
You should now be able to use tikz-cd.

Makes sure to follow the translation rules in the manual for ConTeXt. In addition to that, it seems that you have to replace the apostrophe with "below".

The first few examples in the manual, which compiled with latest ConTeXt:

<texcode>
\usemodule[tikz]
\usetikzlibrary[cd]

\starttext

\starttikzcd
 A \arrow{rd} \arrow{r}{𝜑} \NC B \NR
                                \NC C
\stoptikzcd

\starttikzcd
 A \arrow[r, "\phi"] \arrow[d, red]
   \NC B \arrow[d, "\psi" red] \NR
 C \arrow[r, red, "\eta" blue]
 \NC D
\stoptikzcd

\starttikzcd
 A \arrow[r, "\phi" near start, "\psi" below, "\eta" near end] \NC B
\stoptikzcd

\starttikzcd
 T
 \arrow[drr, bend left, "x"]
 \arrow[ddr, bend right, "y"]
 \arrow[dr, dotted, "{(x,y)}" description] \NC \NC \NR
   \NC X \times_Z Y \arrow[r, "p"] \arrow[d, "q"]
   \NC X \arrow[d, "f"] \NR
 \NC Y \arrow[r, "g"] \NC Z
\stoptikzcd

\starttikzcd[column sep=tiny]
 \NC \pi_1(U_1) \ar[dr] \ar[drr, "j_1", bend left=20]
   \NC
     \NC[1.5em] \NR
 \pi_1(U_1\cap U_2) \ar[ur, "i_1"] \ar[dr, "i_2" below]
   \NC
     \NC \pi_1(U_1) \ast_{ \pi_1(U_1\cap U_2)} \pi_1(U_2) \ar[r, dashed, "\simeq"]
       \NC \pi_1(X) \NR
 \NC \pi_1(U_2) \ar[ur]\ar[urr, "j_2" below, bend right=20]
   \NC
     \NC
\stoptikzcd

\stoptext
</texcode>

== Tips for converting LaTeX TikZ diagrams to ConTeXt ==

TikZ has a vibrant and productive community, thanks to whom numerous examples an be found on the web. Most of them, however are written for LaTeX and must be slightly adapted to work with ConTeXt. Here we list a few tips to do the conversion:

* Replace `\usepackage{tikz}` with `\usemodule[tikz]` and `\usepackage{pgfplots}` with `\usemodule[pgfplots]`.
* Replace all instances of `\begin{XXX}` (where `XXX` is e.g. `tikzpicture`, `scope`, ...) with `\startXXX`.
* Replace all instances of `\end{XXX}` with `\stopXXX`.
* Modify calls to `\definecolor` to match the ConTeXt syntax (see {{cmd|definecolor}}).

== See also ==

[http://archive.contextgarden.net/message/20080219.024326.0e45446b.pt.html Discussion] on the ConTeXt user's list.

[[Category:Modules]]
[[Category:Graphics]]