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向图中添加标签箭头

tag-icon • tag-icon pgfplots
向图中添加标签箭头

我想要创建一个如下的图表：
在此处输入图片描述 但是，我已成功创建图表，但失败了：

  1. 将蓝色箭头添加到我的图表中，
  2. 在曲线和轴箭头之间添加一些空间，然后
  3. 增加整个 tikzpicture 的尺寸，当添加到书籍、文章文档类时，图形非常小。

以下是我当前得到的输出：
在此处输入图片描述
以下是我的 MWE：

\documentclass{article}
\usepackage{pgfplots}
\usepackage{mathtools}
\usepackage{tikz}
\begin{document} 
    
    
    \begin{tikzpicture}
        \pgfplotsset{ticks=none}
        \begin{axis}[
            scaled ticks=false,
            xmin=0,
            ymin=0,
            axis lines=middle,
            axis line style={->},
            x label style={at={(axis description cs:0.5,-0.05)},anchor=north},
            y label style={at={(axis description cs:-0.05,.5)},rotate=90,anchor=south},
            xlabel=Number of stocks in portfolio,
            ylabel=Portfoilio Risk,
            ]
            \addplot[domain=0:10, red, ultra thick,smooth] {e^(-.9*x)+.5};
            \addplot[domain=0:10, gray, dashed,thick] {1.5};
            \addplot[domain=0:10, gray,dashed,thick] {.5};
        \end{axis}
    \end{tikzpicture}
\end{document}

答案1

这不是更好的解决方案（我更喜欢只使用 tikz 包）。

\documentclass{article}
\usepackage{pgfplots}

\usepackage{mathtools}
\usepackage{tikz}

\begin{document} 
    
    \begin{center}
        

    \begin{tikzpicture}[scale=1.5]
        \pgfplotsset{ticks=none}
        \begin{axis}[
            scaled ticks=false,
            xmin=0,
            ymin=0,
            axis lines=middle,
            axis line style={->},
            x label style={at={(axis description cs:0.5,-0.05)},anchor=north},
            y label style={at={(axis description cs:-0.05,.5)},rotate=90,anchor=south},
            xlabel=Number of stocks in portfolio,
            ylabel=Portfoilio Risk,
            ]
            \addplot[domain=0:10, red, ultra thick,smooth] {e^(-.9*x)+.5};
            \addplot[domain=0:10, gray, dashed,thick] {1.5};
            \addplot[domain=0:10, gray,dashed,thick] {.5};
        \end{axis}
            \draw[latex-latex, gray, line width=5pt] (1.2,0)--(1.2,5.7) node[black,pos=.3,fill=white] () {\large\bfseries Total stock risk};
            \draw[latex-latex, gray, line width=5pt] (5,0)--(5,1.9) node[black,pos=.5,fill=white] () {\large\bfseries Undiversifiable Market Risk (Systematic Risk)};
            \draw[-latex,gray,line width=5pt] (2,5.7)--(2,2.2) node[black,pos=.5,fill=white,right] () {\large\bfseries Unsystematic Risk eliminated by diversification};; 
    \end{tikzpicture}
    \end{center}
\end{document}

输出：

在此处输入图片描述

添加：仅限 tikz 版本。代码：

\documentclass{article}
\usepackage{tikz}
\begin{document}    
    \begin{center}  
        \begin{tikzpicture}[yscale=10]
            \draw[thick,->] (0,0)--(12,0) node[pos=.5,below] () {\large\bfseries Number of stocks in portfolio};
            \draw[thick,->] (0,0)--(0,1.7) node[midway,left] () {\large\bfseries \rotatebox{90}{Portfoilio Risk}};
            \draw[red,line width=2pt] plot[domain=0:12,smooth] (\x,{e^(-.9*\x)+.5});
            \draw[blue,dashed] (0,1.5)--(12,1.5);
            \draw[blue,dashed] (0,.5)--(12,.5);

            \draw[latex-latex, gray, line width=5pt] (2,0)--(2,1.5) node[black,pos=.3,fill=white] () {\large\bfseries Total stock risk};
            \draw[latex-latex, gray, line width=5pt] (8,0)--(8,.5) node[black,pos=.5,fill=white] () {\large\bfseries Undiversifiable Market Risk (Systematic Risk)};
            \draw[-latex,gray,line width=5pt] (4,1.5)--(4,.53) node[black,pos=.5,fill=white,right,align=left] () {\large\bfseries Unsystematic Risk eliminated\\\large \bfseries by diversification};; 
        \end{tikzpicture}
    \end{center}
\end{document}

输出：

在此处输入图片描述

答案2

我不太清楚pgfplots，我试过了……

我创建了一个带有 2 个参数的命令，用于将文本放置在曲线上。我使用了\fpeval来自xfp包

编辑：

  • 我修改了\scale=1.5以\width=0.75\linewidth避免标签也被放大
  • 我纠正一个错误\fpeval{exp{-#1*0.9}+.5}，错了，要加上括号！

编辑2

  • Hasan Basri Çetin 对这篇文章的回答从 x 到 f(x) 画一条垂直线，这个xfp包没什么用，我们可以使用以下方法在曲线上定位一个点：

    declare function ={myfun(\x) = e^(-.9*\x)+.5;},domain=0:10

等(axis cs: 3, {myfun(3)})

  • 我们可以用来\pgfplotsinvokeforeach绘制虚线段

代码

    \documentclass{article}
%https://tex.stackexchange.com/questions/680359/adding-labelling-arrows-to-a-plot
\usepackage{showframe}
\usepackage{pgfplots}
\pgfplotsset{compat=1.18}%<-- added
\usetikzlibrary {arrows.meta}%<-- added
\usepackage{tikz}
\begin{document}
\newcommand{\mycalc}[2]{%
  \draw[myarrow,->,shorten >=1pt](axis cs: #1,1.5) -- node[mytext,right]{#2} (axis cs: #1, {myfun(#1)});
}
\begin{center}
  \begin{tikzpicture}[%scale=1.5,
    %https://tex.stackexchange.com/questions/680588/draw-a-vertical-line-from-x-to-fx
    declare function ={myfun(\x) = e^(-.9*\x)+.5;},domain=0:10,
    myarrow/.style = {<->,>={Latex[length=2mm, angle=90:10pt]},blue, line width=4pt},
    mytext/.style = {black,pos=.5,fill=white,font=\bfseries\small},
    ]
    \pgfplotsset{ticks=none}
    \begin{axis}[
        width=0.75\linewidth,%<-- to replace scale=1.5
        xmin=0,
        ymin=0,
        axis lines=middle,
        axis line style={->},
        x label style={at={(axis description cs:0.5,-0.05)},anchor=north,%font=\bfseries\large% we can 
          },
        y label style={at={(axis description cs:-0.05,.5)},rotate=90,anchor=south},
        xlabel=Number of stocks in portfolio,
        ylabel=Portfoilio Risk,
      ]
      \pgfplotsinvokeforeach{0.5,1.5}{
        \draw [dashed] (axis cs:0,#1) -- (axis cs:10,#1);
      }

      % \addplot[domain=0:10, red, ultra thick,smooth] {e^(-.9*x)+.5};
      \addplot[red, ultra thick,smooth] {myfun(x)};

      \draw[myarrow](axis cs: 1.5,1.5) --node[mytext,pos=0.75,xshift=5mm]{Total Stock Risk} (axis cs: 1.5,0);
      \draw[myarrow](7.5,0.5) -- node[mytext]{\parbox{4cm}{\raggedright Undiversifiable Market Risk (Systematic Risk)}} (axis cs: 7.5,0);

      \mycalc{3}{\parbox{4.8cm}{\raggedright Unsystematic Risk eliminated by diversification}}

    \end{axis}
  \end{tikzpicture}
\end{center}
\end{document}

在此处输入图片描述

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