\documentclass{article}
\usepackage{pgfplots}
\usepackage{filecontents}


\begin{document}
\begin{tikzpicture}
\begin{axis}
\addplot+ [mark options={scale = 0.7}, mark = o] table [x=x,y=y, col sep = comma,
only marks] {data_sin_d_t.csv};
\addplot [black] table [x=x, y=y, col sep=comma, mark=none, color = 'black'] {matlab_sin_d_01.csv};
\end{axis}
\end{tikzpicture}
\begin{tikzpicture}
\begin{axis}
\addplot table [x=x, y=y, col sep=comma, only marks] {data_sin_d_t.csv};
\addplot table [black, x=x, y=y, col sep=comma, mark=none, color = 'black'] {matlab_sin_d_01.csv};
\end{axis}
\end{tikzpicture}
\end{document}

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%%% mode: latex
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