[Tex/LaTex] Plot non-continuous function with TikZ

plottikz-pgf

How can I plot a non-continuous function with TikZ (using continuous lines for continous stretches of the function and dashed lines for discontinuities)? Does anybody know an efficient method?

Best Answer

I am not sure if this is what you want, but I would suggest you to use the pgfplots package (internally uses TikZ); a little example (the solid and hollow dot styles are borrowed from a comment by cmhughes):

\documentclass{article}
\usepackage{pgfplots}
\pgfplotsset{compat=1.6}

\pgfplotsset{soldot/.style={color=blue,only marks,mark=*}} \pgfplotsset{holdot/.style={color=blue,fill=white,only marks,mark=*}}

\begin{document}

\begin{tikzpicture}
\begin{axis}
\addplot[domain=0:4,blue] {x*x};
\addplot[domain=4:6,blue] {x};
\addplot[domain=6:10,blue] {-5};
\draw[dotted] (axis cs:4,16) -- (axis cs:4,4);
\draw[dotted] (axis cs:6,6) -- (axis cs:6,-5);
\addplot[holdot] coordinates{(0,0)(4,4)(6,-5)};
\addplot[soldot] coordinates{(4,16)(6,6)(10,-5)};
\end{axis}
\end{tikzpicture}

\end{document}

enter image description here

Related Solutions

[Tex/LaTex] Plot complex self defined function with TikZ

I'm not sure why the function fails when used in a plot, but I would define the function differently, using the declare function key:

\documentclass[10pt]{article}
\usepackage{tikz}

\pgfkeys{
    /pgf/declare function={f(\a,\c) = (\a < \c) * 4 + !(\a < \c) * 3;}
}

\begin{document}
\begin{tikzpicture}
\draw [red, thick, x=0.0085cm, y=1cm]
plot [domain=-200:200, samples=100, const plot] (\x,{f(\x/200, 0)});
\end{tikzpicture}
\end{document}

[Tex/LaTex] Plot Continuous Line With 2 Points

You can use shorten with a negative length to extend the edge.

\documentclass{article}
\usepackage{tikz}
\begin{document}
\begin{tikzpicture}
\node (a) {A};
\node [right of=a,node distance=3em] (b) {B};
\draw [shorten >=-3em,shorten <=-3em] (a) edge (b);
\end{tikzpicture}
\end{document}

output

Best Answer

Related Solutions

[Tex/LaTex] Plot complex self defined function with TikZ

[Tex/LaTex] Plot Continuous Line With 2 Points

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