使用 tikz 在生成的区间内绘制 sin(x)

Question

我有以下代码来生成一个简单的间隔

\begin{tikzpicture}[scale=3, nodes={
       execute at begin node=$,
       execute at end node=$
     }]
\draw[-, thick] (-1,0) -- (1,0) node[above] {};
\foreach \x/\xpar/\xtext in {
    -0.8  / | / +,
    -0.6  / | / ,
    -0.4  / | / +,
    -0.2  / | / -,
     0    / | / ,
     .2   / | / -,
     .4   / | / +,
     .6   / | / -,
     .8   / | / +,   
}   \draw[thick] (\x,0pt) node {\xpar}  node[below=5pt] {\xtext};
\end{tikzpicture}

产生

有没有办法让我在这个区间绘制 sin 函数，以便得到类似

Answer 1

\documentclass[tikz,border=3.14mm]{standalone}
\begin{document}
\begin{tikzpicture}[scale=3, nodes={
       execute at begin node=$,
       execute at end node=$
     }]
\draw[-, thick] (-1,0) -- (1,0) node[above] {};
\foreach \x/\xpar/\xtext in {
    -0.8  / | / +,
    -0.6  / | / ,
    -0.4  / | / +,
    -0.2  / | / -,
     0    / | / ,
     .2   / | / -,
     .4   / | / +,
     .6   / | / -,
     .8   / | / +,   
}   \draw[thick] (\x,0pt) node {\xpar}  node[below=5pt] {\xtext};
\draw[blue] plot[variable=\x,samples=100,domain=-1:1] (\x,{0.2*sin((\x-0.3)*900)});
\end{tikzpicture}
\end{document}

一个更简单也许更美好的可能性：

\documentclass[tikz,border=3.14mm]{standalone}
\begin{document}
\begin{tikzpicture}[scale=3, nodes={
       execute at begin node=$,
       execute at end node=$
     }]
\draw[-, thick] (-1,0) -- (1,0) node[above] {};
\foreach \x/\xpar/\xtext in {-0.8,-0.6,...,0.8}
{\pgfmathtruncatemacro{\y}{sign(sin((\x-0.3)*900))}
\ifnum\y=1
\def\xtext{+}
\else
\def\xtext{-}
\fi
\draw (\x,-2pt) -- (\x,2pt);
\node at (\x,{-\y*5pt}) {\xtext};}
\draw[blue] plot[variable=\x,samples=100,domain=-1:1] (\x,{0.2*sin((\x-0.3)*900)});
\end{tikzpicture}
\end{document}

Answer 2

一些 hacky 高尔夫代码：

\documentclass[tikz,border=7pt]{standalone}
\begin{document}
  \tikz
    \draw[blue](,)foreach~in{+,-,+,-,+,-,+}
      {sin+(,~1)+(0,~-1)node[black,label={[scale=2]~-90:$~$}]{$|$}+(0,0)cos+(,~-1)}
      +(,0)edge[black,latex-](0,);
\end{document}