How make stacked bar chart from dataframe in python

Question

I have the following dataframe:

     Color      Level     Proportion
-------------------------------------
0     Blue          1            0.1
1     Blue          2            0.3
2     Blue          3            0.6
3      Red          1            0.2
4      Red          2            0.5
5      Red          3            0.3

Here I have 2 color categories, where each color category has 3 levels, and each entry has a proportion, which sum to 1 for each color category. I want to make a stacked bar chart from this dataframe that has 2 stacked bars, one for each color category. Within each of those stacked bars will be the proportion for each level, all summing to 1. So while the bars will be "stacked" different, the bars as complete bars will be the same length of 1.

I have tried this:

df.plot(kind='bar', stacked=True)

I then get this stacked bar chart, which is not what I want:

I want 2 stacked bars, and so a stacked bar for "Blue" and a stacked bar for "Red", where these bars are "stacked" by the proportions, with the colors of these stacks corresponding to each level. And so both of these bars would be of length 1 along the x-axis, which would be labelled "proportion". How can I fix my code to create this stacked bar chart?

Michael Cao · Accepted Answer · 2023-01-18 21:30:05Z

2

Make a pivot and then plot it:

df.pivot(index = 'Color', columns = 'Level', values = 'Proportion')
df.plot(kind = 'bar', stacked = True)

Edit: Cleaner legend

edited Jan 18, 2023 at 21:30

answered Jan 18, 2023 at 21:23

Michael Cao

3,7511 gold badge3 silver badges18 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

JohanC · Accepted Answer · 2023-01-18 22:13:12Z

1

You could create a Seaborn sns.histplot using the proportion as weights and the level as hue:

import matplotlib.pyplot as plt
import seaborn as sns
import pandas as pd

df = pd.DataFrame({'Color': ['Blue'] * 3 + ['Red'] * 3,
                   'Level': [1, 2, 3] * 2,
                   'Proportion': [.1, .3, .6, .2, .5, .3]})
sns.set_style('white')
ax = sns.histplot(data=df, x='Color', weights='Proportion', hue='Level', multiple='stack', palette='flare', shrink=0.75)
ax.set_ylabel('Proportion')
for bars in ax.containers:
    ax.bar_label(bars, label_type='center', fmt='%.2f')
sns.move_legend(ax, loc='upper left', bbox_to_anchor=(1, 0.97))
sns.despine()
plt.tight_layout()
plt.show()

answered Jan 18, 2023 at 22:13

JohanC

81.4k8 gold badges54 silver badges90 bronze badges

2 Comments

LostinSpatialAnalysis Over a year ago

Hello, this works great and is totally what I was looking for! Thank you! Do you know if there is a simple way to convert this chart to have these stacked bars going horizontally from left to right? This would mean that the x-axis would be "Proportion", and the y-axis would be "Color", where the y-axis labels would just be "Blue" and "Red". I should have mentioned this in my post.

JohanC Over a year ago

You can replace x= by y=, i.e. sns.histplot(data=df, y='Color', ...) for horizontal bars. You'll also need to replace ax.set_ylabel('Proportion') by ax.set_xlabel('Proportion').

Collectives™ on Stack Overflow

How make stacked bar chart from dataframe in python

2 Answers 2

Comments

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related