How to Draw a 3D Plot Using plotly in Python (Example)

This article provides several examples of 3D plots in plotly using the Python programming language.

Table of contents:

Kirby White Researcher Statistician Programmer

Note: This article was created in collaboration with Kirby White. Kirby is a Statistics Globe author, innovation consultant, data science instructor. His Ph.D. is in Industrial-Organizational Psychology. You can read more about Kirby here!

Before we start, please note that you can view and instantly run the code for this project in a colab notebook, here.

Modules and Example Data

Please install and load these modules as a first step:

import plotly.express as px

We’ll use the gapminder dataset for this example, which is included with the plotly module. This dataset contains information about life expectancy, population size, and GDP per capita for over 100 countries repeatedly from 1952-2007. We’ll store this data frame in an object called df:

df = px.data.gapminder()
df
 
country	continent	year	lifeExp	pop	gdpPercap	iso_alpha	iso_num
# 0	Afghanistan	Asia	1952	28.801	8425333	779.445314	AFG	4
# 1	Afghanistan	Asia	1957	30.332	9240934	820.853030	AFG	4
# 2	Afghanistan	Asia	1962	31.997	10267083	853.100710	AFG	4
# 3	Afghanistan	Asia	1967	34.020	11537966	836.197138	AFG	4
# 4	Afghanistan	Asia	1972	36.088	13079460	739.981106	AFG	4

Two Examples

Let’s look at how the life expectancy and GDP per person has changed over the years, but only the averages within each continent:

fig1 = px.line_3d(
    data_frame = df.groupby(['continent', 'year']).mean().reset_index()
    , x = 'year'
    , y = 'gdpPercap'
    , z = 'lifeExp'
    , color = 'continent'
)
 
fig1.show()
 
# 	continent	year	lifeExp	pop	gdpPercap	iso_num
# 0	Africa	1952	39.135500	4.570010e+06	1252.572466	458.826923
# 1	Africa	1957	41.266346	5.093033e+06	1385.236062	458.826923
# 2	Africa	1962	43.319442	5.702247e+06	1598.078825	458.826923
# 3	Africa	1967	45.334538	6.447875e+06	2050.363801	458.826923

As you can see, our data is visualized as a line plot in a three-dimensional space.

If we want to look at the same data, but only for countries in the European continent, we can use this code:

fig2 = px.line_3d(
    data_frame = df[df['continent'] == 'Europe'].groupby(['country', 'year']).mean().reset_index()
    , x = 'year'
    , y = 'gdpPercap'
    , z = 'lifeExp'
    , color = 'country'
)
 
fig2.show()
 
# 	country	year	lifeExp	pop	gdpPercap	iso_num
# 0	Albania	1952	55.230	1282697.0	1601.056136	8.0
# 1	Albania	1957	59.280	1476505.0	1942.284244	8.0
# 2	Albania	1962	64.820	1728137.0	2312.888958	8.0
# 3	Albania	1967	66.220	1984060.0	2760.196931	8.0

Customizing Colors

If we want to specify the colors to use for each line, we can use the color_discrete_map argument to create a dictionary of group:color pairs. We can use the name of colors or hex codes, as shown below:

fig3 = px.line_3d(
    data_frame = df[df['continent'] == 'Oceania'].groupby(['country', 'year']).mean().reset_index()
    , x = 'year'
    , y = 'gdpPercap'
    , z = 'lifeExp'
    , color = 'country'
    , color_discrete_map = {"Australia":"gray", "New Zealand":"#a53abd"}
)
 
fig3.show()
 
# country	year	lifeExp	pop	gdpPercap	iso_num
# 0	Australia	1952	69.120	8691212.0	10039.59564	36.0
# 1	Australia	1957	70.330	9712569.0	10949.64959	36.0
# 2	Australia	1962	70.930	10794968.0	12217.22686	36.0
# 3	Australia	1967	71.100	11872264.0	14526.12465	36.0

Customizing Line Styles

Similar to the way we specify custom colors for each line, we can change the style of the line within each group. Plotly has several built-in line styles (‘dash’, ‘dashdot’, ‘dot’, ‘longdash’, ‘longdashdot’, and ‘solid’), two of which are demonstrated here:

fig4 = px.line_3d(
    data_frame = df[df['continent'] == 'Oceania'].groupby(['country', 'year']).mean().reset_index()
    , x = 'year'
    , y = 'gdpPercap'
    , z = 'lifeExp'
    , color = 'country'
    , line_dash = 'country'
    , line_dash_map = {"Australia":"dot", "New Zealand":"longdashdot"}
)
 
fig4.show()

Further Resources

In this tutorial, you have learned how to create three-dimensional line plots. However, please note that you could also show other types of plotly graphics such as scatterplots in 3D.

In case you want to learn more on how to create interactive graphics in plotly, please have a look at the related articles below: