mpld3 3D散点图

Question

我正在探索mpld3库，但不知道如何创建3D散点图。使用Matplotlib，我会这样做：

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()

类似地，我尝试使用mpld3 (在Jupyter notebook中)：从mpl_toolkits.mplot3d导入matplotlib.pyplot作为plt导入Axes3D导入mpld3

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

我得到了一个错误

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

有什么想法吗？

以下是完整的错误日志：

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

如上所述，mpld3不支持3D图形，但请检查下面的软件包，它们也用于通过python和plotly将matplotlib图形转换为图形，以及mpld3。

• https://plot.ly/python/

Answer 2

对不起，这不是一个完整的答案，而是一个很长的评论...

我可以通过编辑mpld3._display.py来消除错误，如下所示：

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)

但是，它会在notebook中生成一个带有错误消息的空图：

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

看起来mpld3不是为支持3D而设计的。

Answer 3

遗憾的是，mpld3当前不支持三维打印。它仅支持二维打印。检查以下链接：

• https://github.com/mpld3/mpld3/issues/223
• Python & Matplotlib: Make 3D plot interactive in Jupyter Notebook