Plotting time on the independent axis


This answer is outdated since matplotlib version 3.5. The plot function now handles datetime data directly. See

The use of plot_date is discouraged. This method exists for historic
reasons and may be deprecated in the future.

datetime-like data should directly be plotted using plot.

If you need to plot plain numeric data as Matplotlib date format or
need to set a timezone, call ax.xaxis.axis_date / ax.yaxis.axis_date
before plot. See Axis.axis_date.

Old, outdated answer:

You must first convert your timestamps to Python datetime objects (use datetime.strptime). Then use date2num to convert the dates to matplotlib format.

Plot the dates and values using plot_date:

import matplotlib.pyplot as plt
import matplotlib.dates

from datetime import datetime

x_values = [datetime(2021, 11, 18, 12), datetime(2021, 11, 18, 14), datetime(2021, 11, 18, 16)]
y_values = [1.0, 3.0, 2.0]

dates = matplotlib.dates.date2num(x_values)
plt.plot_date(dates, y_values)

enter image description here

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