我正在尝试标记一些图,但似乎无法弄清楚。我试图得到一些看起来有点像这样的东西:
在 texanmple 网站上找到这里。我想标记每个图对应的函数,如上图所示。
这就是我所拥有的:
\documentclass[tikz]{standalone}
\usepackage{pgfplots}
\begin{document}
\begin{tikzpicture}[plot/.style={very thick,raw gnuplot,mark=none,black}]
\begin{axis}[
minor y tick num=2,
minor x tick num=1,
extra y ticks={0},
extra x ticks={0},
extra tick style={grid style={black},xticklabel=\empty},
width=0.7\textwidth,
ymin=-2, ymax=2,
grid=both, y=1cm,
axis y line=left,
axis x line=bottom
]
\addplot gnuplot [plot, samples=500, restrict y to domain=-10:10] {
plot [-5:5] x**3 - x;
};
\addplot gnuplot [plot, blue, samples=500, restrict y to domain=-10:10] {
plot [-5:5] (x-3)**3 - (x-3);
};
\addplot gnuplot [plot, red, samples=500, restrict y to domain=-10:10] {
plot [-5:5] (x+3)**3 - (x+3);
};
\end{axis}\end{tikzpicture}
\end{document}
生成结果:
由于样式原因,我希望留在轴环境中。
答案1
这是一个解决方案,将 放置node
在曲线上;根据需要在(域的开始) 和(域的结束)pos
之间改变键。您还可以使用锚点,例如、等。0
1
east
west
% arara: pdflatex: {shell: yes}
\documentclass[tikz]{standalone}
\usepackage{pgfplots}
\begin{document}
\begin{tikzpicture}[plot/.style={very thick,raw gnuplot,mark=none,black}]
\begin{axis}[
minor y tick num=2,
minor x tick num=1,
extra y ticks={0},
extra x ticks={0},
extra tick style={grid style={black},xticklabel=\empty},
ymin=-2, ymax=2,
grid=both, y=1cm,
axis y line=left,
axis x line=bottom
]
\addplot gnuplot [plot, samples=500, restrict y to domain=-10:10] {
plot [-2:2] x**3 - x;
}node[pos=0.7,anchor=west]{$y=f(x)$};
\addplot gnuplot [plot, blue, samples=500, restrict y to domain=-10:10] {
plot [1:5] (x-3)**3 - (x-3);
}node[pos=0.3,anchor=west]{$y=g(x)$};
\addplot gnuplot [plot, red, samples=500, restrict y to domain=-10:10] {
plot [-5:-1] (x+3)**3 - (x+3);
}node[pos=0.7,anchor=east]{$y=h(x)$};
\end{axis}\end{tikzpicture}
\end{document}
作为参考,这是一个没有gnuplot
% arara: pdflatex
\documentclass[tikz]{standalone}
\usepackage{pgfplots}
\begin{document}
\begin{tikzpicture}[plot/.style={very thick,mark=none,black,samples=100}]
\begin{axis}[
minor y tick num=2,
minor x tick num=1,
extra y ticks={0},
extra x ticks={0},
extra tick style={grid style={black},xticklabel=\empty},
ymin=-2, ymax=2,
grid=both, y=1cm,
axis y line=left,
axis x line=bottom
]
\addplot [plot,domain=-2:2]{x^3 - x}node[pos=0.7,anchor=west]{$y=f(x)$};
\addplot [plot,blue, domain=1:5] { (x-3)^3 - (x-3)}node[pos=0.3,anchor=west]{$y=g(x)$};
\addplot [plot,red, domain=-5:-1] {(x+3)^3 - (x+3)}node[pos=0.7,anchor=east]{$y=h(x)$};
\end{axis}
\end{tikzpicture}
\end{document}
最后,如果您想要轴外的标签,请查看带有标记图的 PgfPlots 延伸到图形框之外。
答案2
您可以按如下方式向 pgfplot 轴添加图例。这样够了吗?还是您想要图例文本的颜色?
\documentclass[tikz,border=10pt]{standalone}
\usepackage{pgfplots}
\begin{document}
\begin{tikzpicture}[plot/.style={very thick,raw gnuplot,mark=none,black}]
\begin{axis}[
minor y tick num=2,
minor x tick num=1,
extra y ticks={0},
extra x ticks={0},
extra tick style={grid style={black},xticklabel=\empty},
width=0.7\textwidth,
ymin=-2, ymax=2,
grid=both, y=1cm,
axis y line=left,
axis x line=bottom,
legend style={at={(1.1,1)}, anchor={north west}},
]
\addplot gnuplot [plot, samples=500, restrict y to domain=-10:10] {
plot [-5:5] x**3 - x;
};
\addplot gnuplot [plot, blue, samples=500, restrict y to domain=-10:10] {
plot [-5:5] (x-3)**3 - (x-3);
};
\addplot gnuplot [plot, red, samples=500, restrict y to domain=-10:10] {
plot [-5:5] (x+3)**3 - (x+3);
};
\legend{$ x^3 - x $,$ (x-3)^3 - (x-3) $,$ (x+3)^3 - (x+3) $}
\end{axis}\end{tikzpicture}
\end{document}