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WebGL Heatmaps in Python

How to make webGL based heatmaps in Python with Plotly.

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In [1]:
import plotly


In [2]:
import plotly.plotly as py

import PIL.Image
import urllib, cStringIO
import numpy as np

Create a HeatmapGL from an Image

Process the image for generating heatmap:

In [3]:
image_url = ''
f = cStringIO.StringIO(urllib.urlopen(image_url).read())
img =
In [11]:
arr = np.array(img)
z_data = []

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

Create the WebGL Heatmap

In [20]:
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')
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