Draw figures with textbox along arrow

For this figure, I am using Word and Mathtype to draw but the output is not so nice. How can I draw in in LaTeX? I am just new to package TikZ but I guess that it's power can help me here?

• Do you really want the frames around the formulæ? Jan 12 at 21:08
• Why is there A,B,C near X,Y,Z ? a start for you \documentclass[tikz,border=5mm]{standalone} \begin{document} \begin{tikzpicture} \path (0,0) node[draw] (A) {A} (3,2) node[draw] (B) {B} ; \draw[cyan,->] (A)--(B) node[midway,sloped,above]{$\lambda_1=1.111$} ; \end{tikzpicture} \end{document} Jan 12 at 21:13
• @Bernard. It might be better if I have box but not really necessary. Jan 12 at 21:19
• @BlackMild: Thank you. Based on your code, I will work on to build up the figure. I will post the final code later here. Jan 12 at 21:20

An attempt to do it quick and simple:

\documentclass[tikz]{standalone}

\begin{document}
\tikzset{mybox/.style={draw},myarrow/.style={blue,->},myformula/.style={midway,sloped,draw,black,outer sep=4pt}}
\begin{tikzpicture}
\node[mybox](Z) at (0,0) {Z};
\node[mybox](X) at (4,2) {X};
\node[mybox](Y) at (4,-2) {Y};

\node[anchor=east] at (Z.west) {B};
\node[anchor=west] at (X.east) {A};
\node[anchor=west] at (Y.east) {C};

\draw[myarrow] (Z) -- (X) node[myformula,above]{$\lambda_1=-1.115$};
\draw[myarrow] (X) -- (Y) node[myformula,above]{$\lambda_2=-8.273$};
\draw[myarrow] (Z) -- (Y) node[myformula,below]{$\lambda_3=13.232$};
\end{tikzpicture}
\end{document}

This is very easy to obtain from a simple tabular environment and pstricks:

\documentclass[svgnames]{article}
\usepackage{array}
\usepackage{upgreek}
\usepackage{pst-node}

\begin{document}

& & \psDefBoxNodes{X}{\fbox{X}}\enspace A\\
& & \psDefBoxNodes{Y}{\fbox{Y}}\enspace C
\end{tabular}
\psset{arrowinset = 0, arrows =->, linecolor=LightBlue, nodesep=3pt, nrot=:U}
\ncline{Z:Cr}{X:Cl}\naput{\fbox{$\uplambda_1=-1.115$}}
\ncline{Z:Cr}{Y:Cl}\nbput{\fbox{$\uplambda_3=-13.232$}}
\ncline{X:bC}{Y:tC}\naput{\fbox{$\uplambda_2=-8.273$}}
}

\end{document}

• How long do you use pstricks? Jan 13 at 3:10
• @minhthien_2016: I'm not sure I understand what you mean exactly – since when I use pstricks? Jan 13 at 9:12

With use of libraries arrows.meta and quotes:

\documentclass[border=3.141592, tikz]{standalone}
\usetikzlibrary{arrows.meta,
quotes}

\begin{document}
\begin{tikzpicture}[
every edge quotes/.style = {auto, draw=black, thin,
inner sep=2pt, outer sep=2pt, sloped},
]
\scoped[nodes={draw, outer sep=2pt}]%
{
\node[label=left:B] (Z) at (0, 0) {Z};
\node[label=right:A](X) at (4, 2) {X};
\node[label=right:C](Y) at (4,-2) {Y};
}
\path[draw=cyan, thick, -Straight Barb]
(Z) edge["$\lambda_1=-1.115$"]  (X)
(X) edge["$\lambda_2=-8.273$"]  (Y)
(Z) edge["$\lambda_3=13.232$" '](Y);
\end{tikzpicture}
\end{document}

• I like how much different flavors one can have with TikZ, thanks for this solution! Jan 13 at 9:11