如何绘制正弦波图

Question

如何绘制从 (-5, 0.5) 开始到 (5, 1.5) 结束的正弦波图？

\begin{tikzpicture}[scale=0.8]

\begin{axis}[xlabel=$x(t)$, ylabel=$t$, grid=major,xmin=-5
xmax=5, ymin=-2, ymax=2, domain=-5:5]
\addplot[blue, line width=1pt, samples=20]
expression{sin(180*x) ??? };
\end{axis}
\end{tikzpicture}

Answer 1

看来你喜欢画叠加$0.5 + \sin(x)$。这个函数pgfplots是{0.5+sin(180*x)}：

\documentclass[margin=3mm]{standalone}
\usepackage{pgfplots}

\begin{document}
    \begin{tikzpicture}
\begin{axis}[
    xlabel=$x(t)$, ylabel=$t$, 
    grid=major,
    xmin=-5, xmax=5, 
    ymin=-2, ymax=2, 
    domain=-5:4.5,
    samples=201]
\addplot[blue, line width=1pt] {0.5+sin(180*x)};
\end{axis}
    \end{tikzpicture}
\end{document}