\textbf{Loading data from files}

\lstinline|loadtxt('filename')| returns the columns of file in one
sequence. 

\lstinline|x, y = loadtxt('filename', unpack=True)| to obtain a file
with 2 columns in separate sequences. 

\lstinline|loadtxt('filename', delimiter=';')|, if the file has
columns separated by ';' instead of spaces/tabs.