Matplotlib.axes.Axes.plot_date() in Python

Last Updated : 13 Apr, 2020

Matplotlib is a library in Python and it is numerical - mathematical extension for NumPy library. The Axes Class contains most of the figure elements: Axis, Tick, Line2D, Text, Polygon, etc., and sets the coordinate system. And the instances of Axes supports callbacks through a callbacks attribute.

matplotlib.axes.Axes.plot_date() Function

The Axes.plot_date() function in axes module of matplotlib library is used to plot data that contains dates.

Syntax: Axes.plot_date(self, x, y, fmt='o', tz=None, xdate=True, ydate=False, *, data=None, **kwargs) Parameters: This method accept the following parameters that are described below:

x, y: These parameter are the horizontal and vertical coordinates of the data points.

fmt: This parameter is an optional parameter and it contains the string value.

tz: This parameter is the time zone to use in labeling dates.It contain timezone string.

xdate: This parameter is also an optional parameter. And it contain boolean values with default value True. If True, the x-axis will be interpreted as Matplotlib dates.

ydate: This parameter is also an optional parameter. And it contain boolean values with default value True. If True, the y-axis will be interpreted as Matplotlib dates.

Returns: This returns the following:

lines:This returns the list of Line2D objects representing the plotted data.

Below examples illustrate the matplotlib.axes.Axes.plot_date() function in matplotlib.axes: Example-1:

Python3

# Implementation of matplotlib function
    
import datetime
import matplotlib.pyplot as plt
from matplotlib.dates import drange
import numpy as np

date1 = datetime.datetime(2020, 4, 2)
date2 = datetime.datetime(2020, 4, 6)
delta = datetime.timedelta(hours = 24)
dates = drange(date1, date2, delta)

y = np.arange(len(dates))

fig, ax = plt.subplots()
ax.plot_date(dates, y ** 2)

ax.set_title('matplotlib.axes.Axes.plot_date Example1')
plt.show()

Output:

Example-2:

Python3

# Implementation of matplotlib function
    
import datetime
import matplotlib.pyplot as plt
from matplotlib.dates import DayLocator, HourLocator, DateFormatter, drange
import numpy as np

date1 = datetime.datetime(2020, 4, 2)
date2 = datetime.datetime(2020, 4, 6)
delta = datetime.timedelta(hours = 6)
dates = drange(date1, date2, delta)

y = np.arange(len(dates))

fig, ax = plt.subplots()
ax.plot_date(dates, y ** 2)

ax.set_xlim(dates[0], dates[-1])

ax.xaxis.set_major_locator(DayLocator())
ax.xaxis.set_minor_locator(HourLocator(range(0, 25, 6)))
ax.xaxis.set_major_formatter(DateFormatter('%Y-%m-%d'))

ax.fmt_xdata = DateFormatter('%Y-%m-%d %H:%M:%S')
fig.autofmt_xdate()
ax.set_title('matplotlib.axes.Axes.plot_date Example2')
plt.show()