As explained earlier, matplotlib only handles plotting. If you want to plot data stored in a file, you will have to use Python code to read the file and extract the data you need.
Let's assume that we have time series stored in a plain text file named
my_data.txt as follows:
0 0 1 1 2 4 4 16 5 25 6 36
A minimalistic pure Python approach to read and plot that data would go as follows:
import matplotlib.pyplot as plt X, Y = ,  for line in open('my_data.txt', 'r'): values = [float(s) for s in line.split()] X.append(values) Y.append(values) plt.plot(X, Y) plt.show()
This script, together with the data stored in
my_data.txt, will produce the following graph:
The following are some explanations ...