  
  



%--------------------------------------------------------------------------------
\begin{tikzpicture}
\setlength{\base}{0.6cm}

\tikzstyle{wordnode} = [font=\scriptsize]
\tikzstyle{auxnode} = [inner sep=0pt,outer sep=0pt,opacity=0,draw=red,fill=red,circle,minimum size=3pt]
\tikzstyle{opnode} = [inner sep=0pt,outer sep=0pt,draw,fill=green!30!white,font=\scriptsize,minimum size=10pt]
\tikzstyle{standard} = [rounded corners=5pt,thick]
\tikzstyle{emph} = [rounded corners=5pt,thick,draw=red]
\tikzstyle{formulanode} = [font=\scriptsize,align=left,draw=red,rectangle,fill=red!10!white,rounded corners=2pt,drop shadow]

% Skeleton
\begin{scope}[every label/.append style={label distance=1pt,font=\tiny,inner sep=0pt,opacity=0}]
\coordinate (aux12) at (0,0);
\node[auxnode,label={-45:12}] () at (aux12) {};

\coordinate (aux22) at ([yshift=\base]aux12);
\node[auxnode,label={-45:22}] () at (aux22) {};
\coordinate (aux21) at ([xshift=-2\base]aux22);
\node[auxnode,label={-45:21}] () at (aux21) {};
\coordinate (aux23) at ([xshift=\base]aux22);
\node[auxnode,label={-45:23}] () at (aux23) {};
\coordinate (aux24) at ([xshift=\base]aux23);
\node[auxnode,label={-45:24}] () at (aux24) {};
\coordinate (aux25) at ([xshift=\base]aux24);
\node[auxnode,label={-45:25}] () at (aux25) {};
\coordinate (aux26) at ([xshift=\base]aux25);
\node[auxnode,label={-45:26}] () at (aux26) {};
\coordinate (aux27) at ([xshift=\base]aux26);
\node[auxnode,label={-45:27}] () at (aux27) {};
\coordinate (aux28) at ([xshift=\base]aux27);
\node[auxnode,label={-45:28}] () at (aux28) {};
\coordinate (aux29) at ([xshift=2\base]aux28);
\node[auxnode,label={-45:29}] () at (aux29) {};

\coordinate (aux33) at ([yshift=\base]aux23);
\node[auxnode,label={-45:33}] () at (aux33) {};
\coordinate (aux34) at ([yshift=\base]aux24);
\node[auxnode,label={-45:34}] () at (aux34) {};
\coordinate (aux35) at ([yshift=\base]aux25);
\node[auxnode,label={-45:35}] () at (aux35) {};
\coordinate (aux37) at ([yshift=\base]aux27);
\node[auxnode,label={-45:37}] () at (aux37) {};

\coordinate (aux45) at ([yshift=\base]aux35);
\node[auxnode,label={-45:45}] () at (aux45) {};

\coordinate (aux55) at ([yshift=\base]aux45);
\node[auxnode,label={-45:55}] () at (aux55) {};
\ExtractX{$(aux21)$}
\ExtractY{$(aux55)$}
\coordinate (aux51) at (\XCoord,\YCoord);
\node[auxnode,label={-45:51}] () at (aux51) {};
\ExtractX{$(aux23)$}
\ExtractY{$(aux55)$}
\coordinate (aux53) at (\XCoord,\YCoord);
\node[auxnode,label={-45:53}] () at (aux53) {};
\ExtractX{$(aux28)$}
\ExtractY{$(aux55)$}
\coordinate (aux58) at (\XCoord,\YCoord);
\node[auxnode,label={-45:58}] () at (aux58) {};
\ExtractX{$(aux29)$}
\ExtractY{$(aux55)$}
\coordinate (aux59) at (\XCoord,\YCoord);
\node[auxnode,label={-45:59}] () at (aux59) {};

\coordinate (aux68) at ([yshift=\base]aux58);
\node[auxnode,label={-45:68}] () at (aux68) {};
\end{scope}

\begin{scope}
\node[opnode,circle,opacity=0] (f53) at (aux53) {};
\node[opnode,circle,opacity=0] (u55) at (aux55) {};
% forget gate
{
\draw[emph] (aux21) -- (aux23) -- (aux33);
\draw[-latex,emph] (aux12) -- (aux22) -- (aux23) -- (f53);
\node[opnode,circle,draw=red,thick] () at (aux33) {$\sigma$};
}
{
\draw[standard] (aux21) -- (aux23) -- (aux33);
\draw[-latex,standard] (aux12) -- (aux22) -- (aux23) -- (f53);
\node[opnode,circle] () at (aux33) {$\sigma$};
}
% input gate
{
\node[opnode,circle] (i45) at (aux45) {};
\draw[-latex,emph] (aux21) -- (aux24) |- (i45);
\draw[-latex,emph] (aux21) -- (aux25) -- (u55);
\draw[emph] (aux12) -- (aux22) -- (aux23);
\node[opnode,circle,draw=red,thick] () at (aux34) {$\sigma$};
\node[opnode,rectangle,rounded corners=2pt,inner sep=2pt,draw=red,thick] () at (aux35) {$\mathrm{tanh}$};
\node[opnode,circle,draw=red,thick] (i45) at (aux45) {X};
}
{
\node[opnode,circle] (i45) at (aux45) {};
\draw[-latex,standard] (aux21) -- (aux24) |- (i45);
\draw[-latex,standard] (aux21) -- (aux25) -- (u55);
\node[opnode,circle] () at (aux34) {$\sigma$};
\node[opnode,rectangle,rounded corners=2pt,inner sep=2pt] () at (aux35) {$\mathrm{tanh}$};
\node[opnode,circle] (i45) at (aux45) {X};
}
% cell update
{
\draw[-latex,emph] (aux51) -- (aux59);
\node[opnode,circle,draw=red,thick] (f53) at (aux53) {X};
\node[opnode,circle,draw=red,thick] (u55) at (aux55) {\textbf{+}};
}
{
\draw[-latex,standard] (aux51) -- (aux59);
\node[opnode,circle] (f53) at (aux53) {X};
\node[opnode,circle] (u55) at (aux55) {\textbf{+}};
}
% output gate
{
\node[opnode,circle,draw=red,thick] (o27) at (aux27) {X};
\draw[-latex,emph] (u55) -| (o27);
\draw[-latex,emph] (aux21) -- (o27);
\draw[emph] (aux12) -- (aux22) -- (aux23);
\node[opnode,circle,draw=red,thick] () at (aux26) {$\sigma$};
\node[opnode,rectangle,rounded corners=2pt,inner sep=2pt,draw=red,thick] () at (aux37) {$\mathrm{tanh}$};

\draw[-latex,emph] (o27) -- (aux29);
\draw[-latex,emph] (o27) -| (aux68);
}
{
\node[opnode,circle] (o27) at (aux27) {X};
\draw[-latex,standard] (u55) -| (o27);
\draw[-latex,standard] (aux21) -- (o27);
\node[opnode,circle] () at (aux26) {$\sigma$};
\node[opnode,rectangle,rounded corners=2pt,inner sep=2pt] () at (aux37) {$\mathrm{tanh}$};

\draw[-latex,standard] (o27) -- (aux29);
\draw[-latex,standard] (o27) -| (aux68);
}
\end{scope}

\begin{scope}
\node[wordnode,anchor=south] () at ([xshift=0.5\base]aux21) {$\mathbf{h}_{t-1}$};
\node[wordnode,anchor=west] () at (aux12) {$\mathbf{x}_t$};
\node[wordnode,anchor=south] () at ([xshift=0.5\base]aux51) {$\mathbf{c}_{t-1}$};
{
\node[wordnode,anchor=south] () at ([xshift=-0.5\base]aux59) {$\mathbf{c}_{t}$};
}
{
\node[wordnode,anchor=east] () at (aux68) {$\mathbf{h}_{t}$};
\node[wordnode,anchor=south] () at ([xshift=-0.5\base]aux29) {$\mathbf{h}_{t}$};
}
\end{scope}

\begin{pgfonlayer}{background}
\node[draw,very thick,rectangle,fill=blue!10!white,rounded corners=5pt,inner sep=4pt,fit=(aux22) (aux58) (u55) (o27)] (LSTM) {};
\end{pgfonlayer}

\begin{scope}
{
% forget gate formula
\node[formulanode,anchor=south east,text width=10em] () at ([shift={(4\base,1.5\base)}]aux51) {遗忘门\\$\mathbf{f}_t=\sigma(\mathbf{W}_f[\mathbf{h}_{t-1},\mathbf{x}_t]+\mathbf{b}_f)$};
}
{
% input gate formula
\node[formulanode,anchor=north east,text width=10em] () at ([shift={(4\base,-1.5\base)}]aux21) {输入门\\$\mathbf{i}_t=\sigma(\mathbf{W}_i[\mathbf{h}_{t-1},\mathbf{x}_t]+\mathbf{b}_i)$\\$\hat{\mathbf{c}}_t=\mathrm{tanh}(\mathbf{W}_c[\mathbf{h}_{t-1},\mathbf{x}_t]+\mathbf{b}_c)$};
}
{
% cell update formula
\node[formulanode,anchor=south west,text width=10em] () at ([shift={(-4\base,1.5\base)}]aux59) {记忆更新\\$\mathbf{c}_{t}=\mathbf{f}_t\cdot \mathbf{c}_{t-1}+\mathbf{i}_t\cdot \hat{\mathbf{c}}_t$};
}
{
% output gate formula
\node[formulanode,anchor=north west,text width=10em] () at ([shift={(-4\base,-1.5\base)}]aux29) {输出门\\$\mathbf{o}_t=\sigma(\mathbf{W}_o[\mathbf{h}_{t-1},\mathbf{x}_t]+\mathbf{b}_o)$\\$\mathbf{h}_{t}=\mathbf{o}_t\cdot \mathrm{tanh}(\mathbf{c}_{t})$};
}
\end{scope}
\end{tikzpicture}

