graph_bracket_notation_2.tex

\usetikzlibrary{calc}
\usetikzlibrary{arrows.meta}

\tikzset{
    base above/.style={anchor=base, yshift=\pgfkeysvalueof{/pgf/inner ysep}},   % for "m" VS "p" vertical alignment of labels
    start/.style={very near start,base above,sloped},
    end/.style={very near end,base above,sloped}
    }

\begin{tikzpicture}
	\begin{scope}
		\def\scale{3}
		\node (B) at (0,0) {$B$};
		\node (W) at (1*\scale,0) {$W$};
		\node (G) at (0.5*\scale,0.7*\scale) {$G$};
	
		\draw (B)--(G)
			node[start] {$1$}
			node[end] {$1$};
		\draw (B)--(W)
			node[start] {$2$}
			node[end] {$1$};
		\draw (W)--(G)
			node[start] {$2$}
			node[end] {$\overline 2$};
	\end{scope}

	\begin{scope}[xshift=12em]
		\def\scale{3}
		\node (B) at (0,0) {$B$};
		\node (W) at (1*\scale,0) {$\color{red}W^T$};
		\node (G) at (0.5*\scale,0.7*\scale) {$G$};
	
		\draw (B)--(G)
			node[start] {$1$}
			node[end] {$1$};
		\draw (B)--(W)
			node[start] {$2$}
			node[end] {$\color{red}2$};
		\draw (W)--(G)
			node[start] {$\color{red}1$}
			node[end] {$\overline 2$};
	\end{scope}

	\begin{scope}[xshift=24em,yshift=4.5em]
		\def\scale{3}
		\node (B) at (0,0) {$B$};
		\node (GW) at (0.8*\scale,0) {$\color{red}GW^T$};
	
		\draw (B)--(GW)
			node[start] {$12$}
			node[end] {$12$};
	\end{scope}

	\begin{scope}[xshift=27.5em,yshift=1em]
		\def\scale{3}
		\node (B) at (0,0) {$\color{red}B\odot (GW^T)$};
	\end{scope}
\end{tikzpicture}