mpld3 3D scatter plot

Question

I am exploring the mpld3 library and can't figure out how to create 3D scatter plots. With Matplotlib I would do:

import matplotlib.pyplot as plt
from mpl_toolkits.mplot3d import Axes3D

fig = plt.figure()
ax = fig.add_subplot(111, projection='3d')
ax.scatter([1],[5],[7])
plt.show()

Similarly, with mpld3 I tried (in Jupyter notebook): import matplotlib.pyplot as plt from mpl_toolkits.mplot3d import Axes3D import mpld3

mpld3.enable_notebook()
fig = plt.figure()
ax = fig.add_subplot(111, projection='3d')
ax.scatter([1],[5],[7])
mpld3.display(fig) 

and I get the error

TypeError: array([ 0.94,  1.06]) is not JSON serializable

Any ideas?

This is the complete error log:

Traceback (most recent call last) <ipython-input-26-54fc4a65da87> in <module>()
      6 N = 50
      7 ax.scatter([1],[5],[7])
----> 8 mpld3.display(fig)

/usr/local/lib/python2.7/dist-packages/mpld3/_display.pyc in display(fig, closefig, local, **kwargs)
    288     if closefig:
    289         plt.close(fig)
--> 290     return HTML(fig_to_html(fig, **kwargs))
    291 
    292 

/usr/local/lib/python2.7/dist-packages/mpld3/_display.pyc in fig_to_html(fig, d3_url, mpld3_url, no_extras, template_type, figid, use_http, **kwargs)
    234                            d3_url=d3_url,
    235                            mpld3_url=mpld3_url,
--> 236                            figure_json=json.dumps(figure_json),
    237                            extra_css=extra_css,
    238                            extra_js=extra_js)

/usr/lib/python2.7/json/__init__.pyc in dumps(obj, skipkeys, ensure_ascii, check_circular, allow_nan, cls, indent, separators, encoding, default, sort_keys, **kw)
    241         cls is None and indent is None and separators is None and
    242         encoding == 'utf-8' and default is None and not sort_keys and not kw):
--> 243         return _default_encoder.encode(obj)
    244     if cls is None:
    245         cls = JSONEncoder

/usr/lib/python2.7/json/encoder.pyc in encode(self, o)
    205         # exceptions aren't as detailed.  The list call should be roughly
    206         # equivalent to the PySequence_Fast that ''.join() would do.
--> 207         chunks = self.iterencode(o, _one_shot=True)
    208         if not isinstance(chunks, (list, tuple)):
    209             chunks = list(chunks)

/usr/lib/python2.7/json/encoder.pyc in iterencode(self, o, _one_shot)
    268                 self.key_separator, self.item_separator, self.sort_keys,
    269                 self.skipkeys, _one_shot)
--> 270         return _iterencode(o, 0)
    271 
    272 def _make_iterencode(markers, _default, _encoder, _indent, _floatstr,

/usr/lib/python2.7/json/encoder.pyc in default(self, o)
    182 
    183         """
--> 184         raise TypeError(repr(o) + " is not JSON serializable")
    185 
    186     def encode(self, o):

TypeError: array([ 0.94,  1.06]) is not JSON serializable

Answer 1

As mentioned abobe, mpld3 does not support 3D graphs, but check packages below, they are also intended for a visulization through a python and plotly has matplotlib figures conversion to their graphs as well as mpld3 has.

• https://plot.ly/python/

Answer 2

Sorry, it's not a complete answer, rather a long comment...

I could get rid of the error by editing mpld3._display.py as follows:

class NumpyEncoder(json.JSONEncoder):
    """ Special json encoder for numpy types """

    def default(self, obj):
        try: 
            obj=obj.tolist()
            return json.JSONEncoder.encode(self, obj)
        except AttributeError:
            pass
        if isinstance(obj, (numpy.int_, numpy.intc, numpy.intp, numpy.int8,
            numpy.int16, numpy.int32, numpy.int64, numpy.uint8,
            numpy.uint16,numpy.uint32, numpy.uint64)):
            return int(obj)
        elif isinstance(obj, (numpy.float_, numpy.float16, numpy.float32, 
            numpy.float64)):
            return float(obj)

        return json.JSONEncoder.default(self, obj)

However it generates an empty plot with an error message in the notebook :

Javascript error adding output!
TypeError: t.map is not a function
See your browser Javascript console for more details.

looks like mpld3 wasn't designed to support 3D ...