figure5-4-multiplication_gate.tex

\documentclass[tikz, border=50pt]{standalone}

\usepackage{tikz}
\usepackage{medl_colors}
\usetikzlibrary{shapes.multipart, shapes.geometric, arrows.meta}
\usetikzlibrary{matrix, calc, positioning,fit}
\usepackage{arrayjob}

\begin {document}
 
% Layer A neurons'number
\newcommand{\numlayerA}{2} 
\def\negationorder{{{" ","-"," ","-"},{" ","-","-"," "},{"+","-","-","+"},{"","","-","-"}}}

% Layer B neurons'number
\newcommand{\numlayerB}{4}  

% Layer C neurons'number
\newcommand{\numlayerC}{1}   
  
\begin{tikzpicture}
 
% Layer A
\foreach \i in {1,...,\numlayerA}
{
    \node[greenshape, circle, minimum size = 2cm] (layerA\i) at (0,-\i*4) {\large {$x_\i$}};
}

% Layer B
\foreach \i in {1,...,\numlayerB}
{
    \pgfmathparse{\negationorder[0][\i-1]} \edef\lsign{\pgfmathresult}
    \pgfmathparse{\negationorder[2][\i-1]} \edef\rsign{\pgfmathresult}
    
    \node[blueshape, circle, minimum size = 3cm] (layerB\i) at (7, 4-\i*4) {$\sigma^{[1]}( \lsign \lambda x_1 \rsign \lambda x_2) $};
}

% Layer C
\foreach \i in {1,...,\numlayerC}
{
    \node[redshape, circle, minimum size = 2cm] (layerC\i) at (13,-6) {$\hat{y}=f_\theta(x_1, x_2)$};
}

%connect Layer A and Layer B
\foreach \i in {1,...,\numlayerA}
{
    \foreach \j in {1,...,\numlayerB}
    {
      \pgfmathparse{\negationorder[\i-1][\j-1]} \edef\lsign{\pgfmathresult}
      \draw[-Triangle, thickline] (layerA\i) -- (layerB\j) node[pos=.8, above, sloped] {$w_{\j, \i}^{[1]} = \lsign \lambda$};   
    }
} 

%connect Layer B and Layer C
\foreach \i in {1,...,\numlayerB}
{
    \foreach \j in {1,...,\numlayerC}
    {
      \pgfmathparse{\negationorder[3][\i-1]} \edef\lsign{\pgfmathresult}
      \draw[-Triangle, thickline] (layerB\i) -- (layerC\j) node[pos=.6, above, sloped] {$w_{1, \i}^{[2]} = \lsign \mu $};   
    }
} 

\end{tikzpicture}
\end {document}