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How to display the value of the bar on each bar with pyplot.barh()

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How do you display a value in a bar chart?

Click the chart, and then click the Chart Design tab. Click Add Chart Element and select Data Labels, and then select a location for the data label option. Note: The options will differ depending on your chart type. If you want to show your data label inside a text bubble shape, click Data Callout.

What does Barh () do in Python?

barh() function in axes module of matplotlib library is used to make a horizontal bar plot. Parameters: This method accept the following parameters that are described below: y: This parameter is the sequence of y coordinates of the bar. height: This parameter is the height(s) of the bars.


Add:

for i, v in enumerate(y):
    ax.text(v + 3, i + .25, str(v), color='blue', fontweight='bold')

result:

enter image description here

The y-values v are both the x-location and the string values for ax.text, and conveniently the barplot has a metric of 1 for each bar, so the enumeration i is the y-location.


I have noticed api example code contains an example of barchart with the value of the bar displayed on each bar:

"""
========
Barchart
========

A bar plot with errorbars and height labels on individual bars
"""
import numpy as np
import matplotlib.pyplot as plt

N = 5
men_means = (20, 35, 30, 35, 27)
men_std = (2, 3, 4, 1, 2)

ind = np.arange(N)  # the x locations for the groups
width = 0.35       # the width of the bars

fig, ax = plt.subplots()
rects1 = ax.bar(ind, men_means, width, color='r', yerr=men_std)

women_means = (25, 32, 34, 20, 25)
women_std = (3, 5, 2, 3, 3)
rects2 = ax.bar(ind + width, women_means, width, color='y', yerr=women_std)

# add some text for labels, title and axes ticks
ax.set_ylabel('Scores')
ax.set_title('Scores by group and gender')
ax.set_xticks(ind + width / 2)
ax.set_xticklabels(('G1', 'G2', 'G3', 'G4', 'G5'))

ax.legend((rects1[0], rects2[0]), ('Men', 'Women'))


def autolabel(rects):
    """
    Attach a text label above each bar displaying its height
    """
    for rect in rects:
        height = rect.get_height()
        ax.text(rect.get_x() + rect.get_width()/2., 1.05*height,
                '%d' % int(height),
                ha='center', va='bottom')

autolabel(rects1)
autolabel(rects2)

plt.show()

output:

enter image description here

FYI What is the unit of height variable in "barh" of matplotlib? (as of now, there is no easy way to set a fixed height for each bar)


Use plt.text() to put text in the plot.

Example:

import matplotlib.pyplot as plt
N = 5
menMeans = (20, 35, 30, 35, 27)
ind = np.arange(N)

#Creating a figure with some fig size
fig, ax = plt.subplots(figsize = (10,5))
ax.bar(ind,menMeans,width=0.4)
#Now the trick is here.
#plt.text() , you need to give (x,y) location , where you want to put the numbers,
#So here index will give you x pos and data+1 will provide a little gap in y axis.
for index,data in enumerate(menMeans):
    plt.text(x=index , y =data+1 , s=f"{data}" , fontdict=dict(fontsize=20))
plt.tight_layout()
plt.show()

This will show the figure as:

bar chart with values at the top


New in matplotlib 3.4.0

There is now a built-in Axes.bar_label convenience method:

x = [u'INFO', u'CUISINE', u'TYPE_OF_PLACE', u'DRINK', u'PLACE', u'MEAL_TIME', u'DISH', u'NEIGHBOURHOOD']
y = [160, 167, 137, 18, 120, 36, 155, 130]
ind = np.arange(len(y))

fig, ax = plt.subplots()
ax.barh(ind, y)
ax.set_yticks(ind)
ax.set_yticklabels(x)

# new helper method to auto-label bars
ax.bar_label(ax.containers[0])

bar_label example

For grouped bar charts, iterate ax.containers instead:

for container in ax.containers:
    ax.bar_label(container)

For more comprehensive demos, see the official documentation's bar labeling examples.


For anyone wanting to have their label at the base of their bars just divide v by the value of the label like this:

for i, v in enumerate(labels):
    axes.text(i-.25, 
              v/labels[i]+100, 
              labels[i], 
              fontsize=18, 
              color=label_color_list[i])

(note: I added 100 so it wasn't absolutely at the bottom)

To get a result like this: enter image description here