Multi-file submission test

\documentclass{article}
\usepackage{pgfplotstable}
\usepackage{amsmath}

\begin{document}

\pgfplotstableread[header=has colnames]{matrix.dat}\mytable
\pgfplotstabletypeset[
  begin table=\begin{pmatrix},
  end table=\end{pmatrix},
  skip coltypes,
  write to macro=\mymatrix,
  typeset=false
]{\mytable}
$\mymatrix$

\end{document}

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