# tikz Multi-segment Line of Varying Thickness

I'm drawing a multi-segment line with TikZ as below:

\begin{figure*}
\center
\begin{tikzpicture}
\draw[->] (0.25,0) --(0.75,1.2) -- (1.25,1.5) -- (1.75,0.7) -- (2.25,1.1) -- (2.75,0.5) -- (3.25,1.5) -- (4.25,1.8);
\end{tikzpicture}
\end{figure*}


I'd like a few of the segments of the line to be thick, and the rest to be thin. Or, put another way, I'd like the line to be thick from (0.25,0) up until (1.75,0.7).

If I just do \draw[thick] ... the whole line becomes thick, which is not what I want.

Any thoughts?

Thanks!

• This isn't possible without splitting the path into segments, or doing something a little fancy. See tex.stackexchange.com/q/43309/86 for one way to do this. Is that close to what you want? – Loop Space Apr 11 '12 at 16:27
• That looks pretty good, but I couldn't get it working, and it's unclear if you can mix to[] blocks with -- connections. – Richard Apr 11 '12 at 16:46
• @AndrewStacey, I've commented on the answer you linked to above - the code there doesn't seem to be working. – Richard Apr 11 '12 at 16:49
• There was a spurious blank line. I've removed it. – Loop Space Apr 11 '12 at 17:51

The solution is somewhere on the site but about dashed line and solid line. I can't find this answer but I will delete my answer if someone gives the good link

\documentclass{minimal}
\usepackage{tikz}

\tikzset{%
xultra thick/.style={to path={%
\pgfextra{%
\draw[line cap=round, line join=round,ultra thick]
(\tikztostart) -- (\tikztotarget);} (\tikztotarget) \tikztonodes}},
xthin/.style={to path={%
\pgfextra{%
\draw[line cap=round, line join=round,thin]
(\tikztostart) -- (\tikztotarget);} (\tikztotarget)  \tikztonodes}}}
\begin{document}
\begin{tikzpicture}
\draw (0.25,0) -- (0.75,1.2) -- (1.25,1.5)
to[xultra thick]  (1.75,0.7) -- (2.25,1.1) -- (2.75,0.5)
-- (3.25,1.5) to[xthin] (4.25,1.8);
\end{tikzpicture}
\end{document}


In a very basic way you can break the segment into two subsegments:

\begin{tikzpicture}
\draw[thick] (0.25,0) --(0.75,1.2) -- (1.25,1.5) -- (1.75,0.7);
\draw[->] (1.75,0.7) -- (2.25,1.1) -- (2.75,0.5) -- (3.25,1.5) -- (4.25,1.8);
\end{tikzpicture}


Another solution that allows you to decide the thickness of the line is:

 \begin{tikzpicture}
\draw[line width=1pt] (0.25,0) --(0.75,1.2) -- (1.25,1.5) -- (1.75,0.7);
\draw[->,line width=0.5pt](1.75,0.7) -- (2.25,1.1) -- (2.75,0.5) -- (3.25,1.5) -- (4.25,1.8);
\end{tikzpicture}