Matplotlib - Mpld3 fig_to_html() in Django

Question

I am trying to dispaly a scatter of points in mpld3 in my browser.

This is my views.py snippet:

plt.scatter([1, 10], [5, 9])
fig = plt.figure()
html_graph = mpld3.fig_to_html(fig)

return render(request, 'home.html', {'graph': [html_graph]})

And inside of home.html:

{% for elem in graph %}
   {{elem|safe}}
{% endfor %}

But the only thing I see are the controls. I also tried it with:

fig, ax = plt.subplot()

But this only displays the controls along with the graph, without the scattered points.

Any suggestions?

Thanks in Advance

score 4 · Accepted Answer · answered Sep 17 '17 at 14:36

4

You need to first create the figure, then plot the scatter to it.

fig = plt.figure()
plt.scatter([1, 10], [5, 9])
html_graph = mpld3.fig_to_html(fig)

or, maybe better

fig, ax = plt.subplots()
ax.scatter([1, 10], [5, 9])
html_graph = mpld3.fig_to_html(fig)

because in the latter case you are sure to plot the scatter to the axes ax that is part of the figure you are showing.

answered Sep 17 '17 at 14:36

I get a 'main thread not in main loop' exception every once in a while, do you know what that is or if it's related to this approach? – OhMad Sep 17 '17 at 15:08
No, I have no idea where that comes from. It should not depend on this code here, and "once in a while" really does not sound like a problem with the code itself. – ImportanceOfBeingErnest Sep 17 '17 at 15:10
I am trying to import matplotlib to run this code in my app like this `import matplotlib.pyplot as plt, mpld3` but it says `ModuleNotFoundError: No module named 'mpld3'`, How do I solve this ? I already have matplotlib installed – Rahul Sharma Jun 03 '19 at 05:42
@Rahul If you want to use `mpld3` you need to install it. – ImportanceOfBeingErnest Jun 03 '19 at 10:21
@ImportanceOfBeingErnest I did that and it works like a charm but could you help me with one other thing ? – Rahul Sharma Jun 03 '19 at 10:26

1 Answers1