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我想沿着\addplot的线进行剪辑pgfplots。由于尝试失败，我不太清楚如何操作。到目前为止所做的如下。

\documentclass[tikz, convert = false]{standalone}

\usepackage{pgfplots}
\pgfplotsset{compat = 1.10}
\usetikzlibrary{intersections}

\begin{document}
\begin{tikzpicture}
  \begin{axis}[
    no marks,
    axis x line = center,
    axis y line = center,
    xmin = 0,
    xmax = 5,
    xlabel = {x},
    ylabel = {y}
    ]
    \addplot[blue, samples = 500, smooth, name path global = pinvx]
    gnuplot[domain = .5:5] {1/x};
    \addplot[red, samples = 500, smooth, name path global = ninvx]
    gnuplot[domain = .5:5] {-1/x};
    \legend{$\frac{1}{x}$, $\frac{-1}{x}$}

    \path[name path = line1] (axis cs:1.6, 1) -- (axis cs:1.6, -1);
    \path[name path = line2] (axis cs:1.75, 1) -- (axis cs:1.75, -1);
    \path[name intersections = {of = pinvx and line1, by = P1}];
    \path[name intersections = {of = ninvx and line1, by = P2}];
    \path[name intersections = {of = pinvx and line2, by = P3}];
    \path[name intersections = {of = ninvx and line2, by = P4}];

    \draw[green, opacity =.7] (P1) -- (P2);
    \draw[green, opacity =.7] (P3) -- (P4);

    \begin{scope}
      \clip pinvx;
      \fill[green, opacity =.7] (P1) -- (P3) -- (1.75, 0) -- (1.6, 0);
    \end{scope}
  \end{axis}
\end{tikzpicture}
\end{document}

我的最终目标是填充线条和绘图之间的区域1/x。-1/x我尝试使用带有第一个绘​​图名称的剪辑，但不起作用。

这是没有尝试遮蔽该区域的图。

在此处输入图片描述

答案1

您可以使用fillbetween的库pgfplots，它的使用非常简单：

  1. 命名路径，A例如B
  2. \addplot fill between [of=A and B,...];，其中...代表其他选项。

有关更多信息，请参阅第 364 页上的第 5.6 节“填充之间”pgfplots手动的。

执行

\documentclass[tikz]{standalone}
\usepackage{pgfplots}
\usepgfplotslibrary{fillbetween}
\begin{document}
\begin{tikzpicture}
  \begin{axis}[
    no marks,
    axis x line = center,
    axis y line = center,
    xmin = 0,
    xmax = 5,
    xlabel = $x$,
    ylabel = $y$
    ]
    \addplot[blue, samples = 500, smooth, name path global = pinvx]
    gnuplot[domain = .5:5] {1/x};
    \addplot[red, samples = 500, smooth, name path global = ninvx]
    gnuplot[domain = .5:5] {-1/x};
    \legend{$\frac{1}{x}$, $\frac{-1}{x}$}

    \addplot fill between [of=pinvx and ninvx,soft clip={domain=1.6:1.75}];
  \end{axis}
\end{tikzpicture}
\end{document}

输出

在此处输入图片描述

答案2

这是 的结果clip。首先，您需要定义一个裁剪区域，其坐标与绿线相关联。然后您绘制并填充两个函数，\closedcycle以便填充曲线下方的区域。但是，实际生成的裁剪区域是上述区域的交集——矩形、1/x 和 -1/x 以下的区域。

在此处输入图片描述

代码

\documentclass[tikz, convert = false]{standalone}

\usepackage{pgfplots}
\pgfplotsset{compat = 1.8}
\usetikzlibrary{intersections}

\begin{document}
\begin{tikzpicture}
  \begin{axis}[
    no marks,
    axis x line = center,
    axis y line = center,
    xmin = 0,
    xmax = 5,
    xlabel = {x},
    ylabel = {y}
    ]
    \addplot[blue, samples = 500, smooth, name path global = pinvx,domain = .5:5] {1/x};
    \addplot[red, samples = 500, smooth, name path global = ninvx, domain = .5:5] {-1/x};
    \legend{$\frac{1}{x}$, $\frac{-1}{x}$}

    \path[name path = line1] (axis cs:1.6, 1) -- (axis cs:1.6, -1);
    \path[name path = line2] (axis cs:1.75, 1) -- (axis cs:1.75, -1);
    \path[name intersections = {of = pinvx and line1, by = P1}];
    \path[name intersections = {of = ninvx and line1, by = P2}];
    \path[name intersections = {of = pinvx and line2, by = P3}];
    \path[name intersections = {of = ninvx and line2, by = P4}];

    \draw[green, opacity =.7] (P1) -- (P2);
    \draw[green, opacity =.7] (P3) -- (P4);

    \begin{scope}
      \clip (axis cs: 1.6,-1) rectangle (axis cs:1.75,1);
    \addplot[samples = 500, smooth, name path global = pinvx,domain = .5:5,fill=green, opacity =.7] {1/x}\closedcycle;
    \addplot[samples = 500, smooth, name path global = ninvx, domain = .5:5,fill=green, opacity =.7] {-1/x}\closedcycle;
    \end{scope}
  \end{axis}
\end{tikzpicture}
\end{document}

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