%%% Preamble Requirements %%%
% \usepackage{geometry}
% \usepackage{amsfonts}
% \usepackage{amsmath}
% \usepackage{amssymb}
% \usepackage{tikz}

% Optional packages such as sfmath set through python interface
% \usepackage{sfmath}

% \usetikzlibrary{arrows,chains,positioning,scopes,shapes.geometric,shapes.misc,shadows}

%%% End Preamble Requirements %%%

\input{"/home/jav/.local/lib/python3.8/site-packages/pyxdsm/diagram_styles"}
\begin{tikzpicture}

\matrix[MatrixSetup]{
%Row 0
\node [DataIO] (output_data) {$\begin{array}{c}\text{modelling settings}\end{array}$};&
&
&
&
\\
%Row 1
\node [Function] (data) {$\begin{array}{c}\text{Modeling}\end{array}$};&
\node [DataInter] (data-ode) {$\begin{array}{c}\text{CPE settings,} \\ \text{tracked state}$$\,(\beta)$$\end{array}$};&
\node [DataInter] (data-qt) {$\begin{array}{c}$$\boldsymbol{Q} / \boldsymbol{T}$$\text{ settings,} \\ \text{tracked state}$$\,(\beta)$$\end{array}$};&
&
\\
%Row 2
&
\node [Function,stack] (ode) {$\begin{array}{c}\text{Model} \\ \text{CPE}$$\,(\beta)$$\end{array}$};&
&
&
\node [DataIO] (right_output_ode) {$\begin{array}{c}\text{save: CPE}$$\,(\beta)$$ \\ \text{plots}\end{array}$};\\
%Row 3
&
&
\node [Function,stack] (qt) {$\begin{array}{c}\text{Model} \\ $$\boldsymbol{Q} / \boldsymbol{T} \,(\beta)$$\end{array}$};&
&
\node [DataIO] (right_output_qt) {$\begin{array}{c}\text{save:}$$ \boldsymbol{Q} / \boldsymbol{T} \,(\beta)$$ \\ \text{plots}\end{array}$};\\
%Row 4
&
&
&
&
\\
};

% XDSM process chains
{ [start chain=process]
 \begin{pgfonlayer}{process} 
\chainin (data);
\chainin (ode) [join=by ProcessHVA];
\end{pgfonlayer}
}{ [start chain=process]
 \begin{pgfonlayer}{process} 
\chainin (data);
\chainin (qt) [join=by ProcessHVA];
\end{pgfonlayer}
}

\begin{pgfonlayer}{data}
\path
% Horizontal edges
(data) edge [DataLine] (data-ode)
(data) edge [DataLine] (data-qt)
(ode) edge [DataLine] (right_output_ode)
(qt) edge [DataLine] (right_output_qt)
% Vertical edges
(data-ode) edge [DataLine] (ode)
(data-qt) edge [DataLine] (qt)
(data) edge [DataLine] (output_data);
\end{pgfonlayer}

\end{tikzpicture}