你好我不明白为什么 tikz 找不到曲线和右边的交点?谢谢
\documentclass[border=5mm]{standalone}
\usepackage{tikz}
\usetikzlibrary{calc,intersections}
[![enter image description here][1]][1]
\begin{document}
\begin{tikzpicture}[xscale=0.015,yscale=0.01]
\draw[domain=0:500,samples=1000,variable=\x,name path=A] plot ({\x},{475.-712.*exp(-0.133e-2*\x*10)+238.*exp(-0.400e-2*\x*10)});
\draw[-latex] (0,0)coordinate(O)-- (500,0) node[above]{$t$};
\draw[-latex] (O) -- (0,500) node[right]{$\theta_s(t)$};
\draw[dashed,thick,name path=S100] (0,{475}) -- (500,{475});
\draw[dashed,thick,name path=S95] (0,{475*0.95}) -- (500,{475*0.95});
\path[name intersections={of=S95 and A,by=E}];
\draw (E) |- (O-|E);
\end{tikzpicture}
\end{document}
答案1
我使用平滑选项和 tikz 找到交点
\begin{tikzpicture}[xscale=0.015,yscale=0.01]
\draw[domain=0:500,samples=1000,variable=\x,name path=A,smooth] plot ({\x},{475.-712.*exp(-0.133e-2*\x*10)+238.*exp(-0.400e-2*\x*10)});
\draw[-latex] (0,0)coordinate(O)-- (500,0) node[above]{$t$};
\draw[-latex] (O) -- (0,500) node[right]{$\theta_s(t)$};
\draw[dashed,thick,name path=S100] (0,{475}) -- (500,{475});
\draw[dashed,thick,name path=S95] (0,{475*0.95}) -- (500,{475*0.95});
\path[name intersections={of=S95 and A,by=E}];
\draw (E) |- (O-|E);
\end{tikzpicture}