WebGL Heatmaps in Python/v3

How to make webGL based heatmaps in Python with Plotly.

Note: this page is part of the documentation for version 3 of Plotly.py, which is not the most recent version.
See our Version 4 Migration Guide for information about how to upgrade.

New to Plotly?¶

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Version Check¶

Plotly's python package is updated frequently. Run pip install plotly --upgrade to use the latest version.

In [1]:
import plotly


In [25]:
import plotly.plotly as py

import requests
from PIL import Image
from io import BytesIO

Create a HeatmapGL from an Image¶

Process the image for generating heatmap:

In [21]:
image_url = 'https://images.plot.ly/plotly-documentation/images/heatmap-galaxy.jpg'

response = requests.get(image_url)
img = Image.open(BytesIO(response.content))
In [23]:
arr = np.array(img)
z_data = []

for i in range(500):
    k = []
    for j in range(500):

Create the WebGL Heatmap

In [24]:
trace = dict(type='heatmapgl', z=z_data, colorscale='Picnic')
data = [trace]

layout = dict(width=700, height=700)
fig = dict(data=data, layout=layout)
py.iplot(fig, filename='basic heatmapgl')


See https://plotly.com/python/reference/#heatmapgl for more information and chart attribute options!