I would like to put an angle between a curve and a particular axis (let's say the x-axis). I tried several options but chose to use angles however it's still not working.
Can somebody help me to identify the problem ?
Script :
\documentclass[margin=3mm]{standalone} \usepackage{pgfplots} \pgfplotsset{compat=1.18} \usetikzlibrary{angles, arrows.meta, quotes} \usepackage{siunitx} \begin{center} \begin{tikzpicture}[scale=1, the_angle/.style args = {#1/#2}{draw,<->, angle radius=#1, angle eccentricity=#2, %anchor=south west, }, % angle label position dot/.style = {circle, fill, inner sep=-1.2pt} ] \pgfplotsset{ticks=none} \begin{axis}[axis lines=middle,xmin=0,xmax=15,ymin=0,ymax=7, ultra thick, xlabel=$\scriptstyle \log(t)$, ylabel=$\scriptstyle \log(R)$, x label style={at={(1,-0.01)},anchor=north}, y label style={at={(-0.15,1)},anchor=west}, ] % \addplot+[no marks,blue,domain=0:8,samples=300, thick] {(1/3)*x} coordinate (A); \coordinate (O) at (0,0); % intersection with coordinate axis \coordinate (C) at (2,0); \pic [the_angle=9mm/1.2, $\qty{30}{\degree}$] {angle = C--O--A}; \addplot+[no marks,dashed,blue,domain=8:14,samples=300, thin] {(1/3)*(x-8)+8/3}; \addplot+[no marks,ForestGreen,domain=8:14,samples=300, thick] {(1/2)*(x-8)+8/3}; \addplot+[no marks,dashed,ForestGreen,domain=0:8,samples=300, thin] {(1/2)*(x-8)+8/3}; % \node[dot, label=left:$\lambda_{E-G}$] at (0,8/3) {}; \draw[gray, thick, dash pattern=on 6pt off 3pt] (0,8/3) -- (8,8/3); \end{axis} \end{tikzpicture} \end{center} \end{document} this option was suggested in this post : here
and i obtain the following error :
Thank you for your help,
Sincerely.
