0

I would like to make the graph of this curve with Tikz; I am not quite sure how to do the diagram, detailing of the arrows and points. I would really appreciate your help.

enter image description here

Improve this question

2 Answers 2

Reset to default
7

This is almost literally copied from section 50.6.1 of the pgf manual.

\documentclass[tikz,border=3mm]{standalone}
\usetikzlibrary{decorations.markings}
\begin{document}
\begin{tikzpicture}[decoration={markings,% switch on markings
    mark=between positions 0.1 and 0.9 step 12mm with {\arrow{stealth}}},
    dot/.style={circle,inner sep=1pt,fill}]
  \draw[postaction={decorate},red] (0,0) node[dot,label=right:{$P_2(2,2)$}]{}
    arc[start angle=45,end angle=-135,radius=2] 
    node[dot,label=left:{$P_2(-2,-2)$}]{}
    -- cycle; 
\end{tikzpicture}
\end{document}

enter image description here

Improve this answer
2
  • My post overlapped with yours. But I see you did essentially the same thing I did. May I suggest placing the decorations into its own style with tikzset as I did in my solution? I will delete mine since it's so similar and you posted first. Also, you may want to add the \gamma label to the arc.
    – Sandy G
    Nov 23, 2021 at 1:31
  • 1
    @SandyG Thanks for the heads up! I do not see a reason why you want to remove your nice answer. As for the style, yes, you can define a global style, and in many situations this is precisely what you want. However, there can also be a benefit from having the definition local, which the example in the pgf manual and this answer does.
    – user255043
    Nov 23, 2021 at 4:49
4

It is often useful to use \tikzset for a style you will use more than once. In the code below, adding multarrow to \draw options will add five arrows to the path.

enter image description here

\documentclass{article}

\usepackage{tikz}
\usetikzlibrary{decorations.markings}

\tikzset{multarrow/.style={decoration={markings,mark=between positions 0.1 and 1 step 0.2 with {\arrow{>}}},postaction={decorate}}}

\begin{document}

\begin{tikzpicture}
\draw[multarrow, red, thick] (-2,-2)node[fill, circle, inner sep=1pt, label={[below left] $P_1(-2,-2)$}]{} 
  -- (2,2)node[fill, circle, inner sep=1pt, label={[right] $P_2(2,2)$}]{} 
  arc(45:-135:{2*sqrt(2)})node[below right, pos=.3]{$\gamma$};
\end{tikzpicture}

\end{document}
Improve this answer

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .