\begin{axis}[
    axis lines=center, no marks, 
    width=\linewidth, height=.66\linewidth,
]
    \addplot table [x expr=\coordindex, y=price, col sep=comma] {\file};
\end{axis}

\begin{axis}[
    axis lines=center, no marks, 
    width=\linewidth, height=3cm,
    hide y axis,
]
    \addplot table [x expr=\coordindex, y=macd, col sep=comma] {\file};
    \addplot table [x expr=\coordindex, y=signal, col sep=comma] {\file};
    \addplot table [x expr=\coordindex, y=delta, col sep=comma] {\file};
\end{axis}