Python | Matplotlib.pyplot ticks

Matplotlib is an amazing visualization library in Python for 2D plots of arrays. Matplotlib is a multi-platform data visualization library built on NumPy arrays and designed to work with the broader SciPy stack. It was introduced by John Hunter in the year 2002.

One of the greatest benefits of visualization is that it allows us visual access to huge amounts of data in easily digestible visuals. Matplotlib consists of several plots like line, bar, scatter, histogram etc.

Ticks are the values used to show specific points on the coordinate axis. It can be a number or a string. Whenever we plot a graph, the axes adjust and take the default ticks. Matplotlib’s default ticks are generally sufficient in common situations but are in no way optimal for every plot. Here, we will see how to customize these ticks as per our need.

Parameters :

Parameter Value Use
axis x, y, both Tells which axis to operate
reset True, False If True, set all parameters to default
direction in, out, inout Puts the ticks inside or outside or both
length Float Sets tick’s length
width Float Sets tick’s width
rotation Float Rotates ticks wrt the axis
colors Color Changes tick color
pad Float Distance in points between tick and label

Example #1: Default plot

# importing required modules
import matplotlib.pyplot as plt
# values of x and y axes
x = [5, 10, 15, 20, 25, 30, 35, 40, 45, 50]
y = [1, 4, 3, 2, 7, 6, 9, 8, 10, 5]
plt.plot(x, y)

Output :

Example #2: Playing with the ticks

Suppose we don’t want to display the values of ticks or want our ticks to be tilted or want any other customization. We can do it this way.

# importing libraries
import random
import matplotlib.pyplot as plt
fig = plt.figure()
# function to get random values for graph
def get_graphs():
    xs =[]
    ys =[]
    for i in range(10):
    return xs, ys
# defining subplots
ax1 = fig.add_subplot(221)
ax2 = fig.add_subplot(222)
ax3 = fig.add_subplot(223)
ax4 = fig.add_subplot(224)
# hiding the marker on axis
x, y = get_graphs()
ax1.plot(x, y)
ax1.tick_params(axis ='both', which ='both', length = 0)
# One can also change marker length
# by setting (length = any float value)
# hiding the ticks and markers
x, y = get_graphs()
ax2.plot(x, y)
# hiding the values and displaying the marker
x, y = get_graphs()
ax3.plot(x, y)
# tilting the ticks (usually needed when
# the ticks are densely populated)
x, y = get_graphs()
ax4.plot(x, y)
ax4.tick_params(axis ='x', rotation = 45)
ax4.tick_params(axis ='y', rotation =-45)


Example #3: Changing the values of ticks.

In the first example, the x-axis and y-axis were divided by the value of 10 and 2 respectively. Let’s make it 5 and 1.

# importing libraries
import matplotlib.pyplot as plt
import numpy as np
# values of x and y axes
x = [5, 10, 15, 20, 25, 30, 35, 40, 45, 50]
y = [1, 4, 3, 2, 7, 6, 9, 8, 10, 5]
plt.plot(x, y, 'b')
# 0 is the initial value, 51 is the final value
# (last value is not taken) and 5 is the difference
# of values between two consecutive ticks
plt.xticks(np.arange(0, 51, 5))
plt.yticks(np.arange(0, 11, 1))


The main difference from the 1st example is :

plt.xticks(np.arange(0, 51, 5))
plt.yticks(np.arange(0, 11, 1))

Changing the values in np.arange will change the range of ticks.

Reference: Matplotlib ticks.

This article is attributed to GeeksforGeeks.org



leave a comment



load comments

Subscribe to Our Newsletter