Matplotlib.axis.Axis.set_major_formatter() function in Python

Last Updated : 03 Jun, 2020

Matplotlib is a library in Python and it is numerical – mathematical extension for NumPy library. It is an amazing visualization library in Python for 2D plots of arrays and used for working with the broader SciPy stack.

matplotlib.axis.Axis.set_major_formatter() Function

The Axis.set_major_formatter() function in axis module of matplotlib library is used to set the formatter of the major ticker.

Syntax: Axis.set_major_formatter(self, formatter)

Parameters: This method accepts the following parameters.

formatter: This parameter is the Formatter.

Return value: This method does not returns any value.

Below examples illustrate the matplotlib.axis.Axis.set_major_formatter() function in matplotlib.axis:
Example 1:

Python3

# Implementation of matplotlib function  
import numpy as np 
from matplotlib.axis import Axis   
import matplotlib.pyplot as plt 
import matplotlib.ticker as ticker 
     
np.random.seed(19680801) 
  
fig, ax = plt.subplots() 
ax.plot(100*np.random.rand(20)) 
  
formatter = ticker.FormatStrFormatter('?%1.2f') 
Axis.set_major_formatter(ax.yaxis, formatter) 
  
for tick in ax.yaxis.get_major_ticks(): 
    tick.label1.set_color('green') 
  
plt.title("Matplotlib.axis.Axis.set_major_formatter()\n\ 
Function Example", fontsize = 12, fontweight ='bold')  
  
plt.show()

Output:

Example 2:

Python3

# Implementation of matplotlib function  
from matplotlib.axis import Axis 
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, 'g')  
      
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(plt.NullFormatter())  
      
ax.fmt_xdata = DateFormatter('% Y-% m-% d % H:% M:% S')  
fig.autofmt_xdate()  
   
plt.title("Matplotlib.axis.Axis.set_major_formatter()\n\ 
Function Example", fontsize = 12, fontweight ='bold')  
  
plt.show()