Plotting Scatter Plots With Altair in Python
source link: https://www.journaldev.com/59301/scatter-plots-with-altair-in-python
Go to the source link to view the article. You can view the picture content, updated content and better typesetting reading experience. If the link is broken, please click the button below to view the snapshot at that time.
A scatter plot (scatter graph, scatter chart, scattergram, or scatter diagram) is a type of plot which makes use of the Cartesian coordinates to display values typically two variables
for a dataset. In this tutorial, we will understand how to plot scatter plots using the Altair library in Python.
Also read: Python Altair tutorial: Creating Interactive Visualizations
Code Implementation of Altair Scatter Plots
Altair
is a statistical visualization library in Python. It is declarative in nature and is based on Vega and Vega-Lite
visualizations. We’ll use this library to plot our scatter plots now.
Importing the Modules
We will start off by loading the Pandas
and NumPy
libraries. We will also import Altair
and vega_datasets
to get the dataset in the later sections.
import
pandas as pd
import
numpy as np
import
altair as alt
import
matplotlib.pyplot as plt
from
vega_datasets
import
data
Loading Dataset for Altair Histogram Plot
In this tutorial, we will be making use of the vega_datasets which is a Python library that gives access to over 60 datasets
of varying sizes. We will be using the weather data set
from Seattle using the code below.
seattle_weather_data
=
data.seattle_weather()
print
(seattle_weather_data.head())
Create a simple Scatter Plot
In this tutorial, we want to build a scatter chart using the mark_point
function. With the help of encode
function, we can decide the variable we want to consider.
alt.Chart(seattle_weather_data).mark_bar().encode(
alt.X(
"wind:Q"
,
bin
=
alt.BinParams()),
y
=
'count(*):Q'
)
Adding colors on the basis of a column
The next step in the visualization is adding colors to the plot on the basis of a certain column using the codes below. We will be plotting on the basis of two columns, weather
and precipitation
.
alt.Chart(seattle_weather_data).mark_bar().encode(
alt.X(
"wind:Q"
,
bin
=
alt.BinParams()),
y
=
'count(*):Q'
,
color
=
'weather'
)
alt.Chart(seattle_weather_data).mark_bar().encode(
alt.X(
"wind:Q"
,
bin
=
alt.BinParams()),
y
=
'count(*):Q'
,
color
=
'precipitation'
)
Conclusion
I hope you are now clear with what Altair is and how to plot scatter plots using the same in the Python programming language. There are many more features of the library in terms of interactivity components.
Thank you for reading!
Recommend
About Joyk
Aggregate valuable and interesting links.
Joyk means Joy of geeK