如何使用 LaTeX 绘图？

Question

我正在写一篇论文，对 LaTeX 还不太熟悉。我想知道这些图形是如何制作的。它们是用 LaTeX 制作的吗？如果是，那么怎么做？

Answer 1

针对每个问题都有很多帖子，现在又多了一个帖子。例如，神经网络与这个帖子。

\documentclass[tikz,border=3mm]{standalone}
\usetikzlibrary{arrows.meta,chains}
\begin{document}
\begin{tikzpicture}[neuron/.style={circle,inner sep=1em,draw},
    neuron missing/.style={
    scale=1.25,
    text height=0.333cm,
    execute at begin node=$\vdots$,
  }]
 \begin{scope}[x=3cm,y=2cm]  
 \foreach \X/\Y [count=\Z,remember=\Y as \LastY] in {Input/2,Hidden/3,Hidden/4,Output/2} 
 {\foreach \YY in {1,...,\Y}
 {\node[neuron] (n-\Z-\YY) at (\Z,-\YY+\Y/2+1/2) {};
 \ifnum\YY=1
  \node[above=1em of n-\Z-\YY,font=\sffamily] {\X\ layer};
 \else
  \path (n-\Z-\the\numexpr\YY-1) -- (n-\Z-\YY) 
   node[midway,neuron missing] {};
 \fi
 \ifnum\Z>1
  \foreach \YYY in {1,...,\LastY}
  {\draw[-{Triangle},semithick] (n-\the\numexpr\Z-1\relax-\YYY) -- (n-\Z-\YY) ;}
 \fi
 }}
 \end{scope} 
 \path[nodes={inner sep=1pt}]
    (n-2-2.-80) node[below right]{$x_i^\ell$} 
    (n-3-3.-80) node[below right]{$x_j^{\ell+1}$}
    (n-3-3.west) node[left=2pt]{$w_{ij}^{\ell}$}
    (n-4-2.-90) node[below]{$\widehat{y_k}$};
\end{tikzpicture}

\begin{tikzpicture}[box/.style={draw,thick,minimum width=5em,minimum
    height=1.2em},arj/.style={semithick,-latex}]
  \begin{scope}[start chain=A going below,oc/.style={join=by arj,on chain},
    font=\sffamily,node distance=1.75em]
   \node[box,oc]{Layer};
   \node[box,oc,label={north west:{$F(x_\ell)$}}]{Layer};
   \node[circle,oc,draw,thick,node font=\bfseries\large,inner sep=1pt,
    label={left:{$F(x_\ell)+x_\ell$}}]{+};
   \node[oc]{$x_{\ell+1}$};
  \end{scope}   
  \draw[arj,latex-] (A-1.north) -- ++ (0,1.75em)
      coordinate[midway,label=left:{$x_\ell$}](aux);
  \draw[arj] (aux) -- ++ (2em,0) to[out=0,in=0,looseness=1.5]
  node[midway,right]{$h(x_\ell)=x_\ell$}(A-3);    
\end{tikzpicture}
\end{document}