基于熊猫列的gmaps标记大小

Question

我正在尝试在 gmaps 中创建气泡图，气泡的大小基于 pandas 数据框中列中的值。我收到错误 'TraitError: Symbol 实例的'scale' trait 必须是 int，但指定的值为 2335。'

我的数据集是这样的：

https://raw.githubusercontent.com/CSSEGISandData/COVID-19/master/csse_covid_19_data/csse_covid_19_time_series/time_series_covid19_confirmed_global.csv

我将数据框命名为“cgr”，然后我的代码是这样的：

data_layer = gmaps.symbol_layer(
cgr[['Lat','Long']], fill_color='green', stroke_color='green', scale=cgr['5/1/20']
)

fig = gmaps.figure()

fig.add_layer(data_layer)

fig

我不明白为什么 gmaps 不能将 numpy.int64 数字识别为整数，并且我无法将它们转换为原生 python 整数。有什么想法吗？

这是完整的追溯

TraitError                                Traceback (most recent call last)
<ipython-input-7-202e1cec5d37> in <module>
      1 data_layer = gmaps.symbol_layer(
----> 2 cgr[['Lat','Long']], fill_color='green', stroke_color='green', scale=cgr['5/1/20']
      3 )
      4 fig = gmaps.figure()
      5 fig.add_layer(data_layer)

~\anaconda3\lib\site-packages\gmaps\marker.py in symbol_layer(locations, hover_text, fill_color, fill_opacity, stroke_color, stroke_opacity, scale, info_box_content, display_info_box)
    479         fill_opacity, stroke_color, stroke_opacity, scale,
    480         info_box_content, display_info_box)
--> 481     symbols = [Symbol(**option) for option in options]
    482     return Markers(markers=symbols)
    483 

~\anaconda3\lib\site-packages\gmaps\marker.py in <listcomp>(.0)
    479         fill_opacity, stroke_color, stroke_opacity, scale,
    480         info_box_content, display_info_box)
--> 481     symbols = [Symbol(**option) for option in options]
    482     return Markers(markers=symbols)
    483 

~\anaconda3\lib\site-packages\gmaps\marker.py in __init__(self, location, **kwargs)
    162         kwargs = _resolve_info_box_kwargs(**kwargs)
    163         kwargs['location'] = location
--> 164         super(Symbol, self).__init__(**kwargs)
    165 
    166 

~\anaconda3\lib\site-packages\ipywidgets\widgets\widget.py in __init__(self, **kwargs)
    410         """Public constructor"""
    411         self._model_id = kwargs.pop('model_id', None)
--> 412         super(Widget, self).__init__(**kwargs)
    413 
    414         Widget._call_widget_constructed(self)

~\anaconda3\lib\site-packages\traitlets\traitlets.py in __init__(self, *args, **kwargs)
    995             for key, value in kwargs.items():
    996                 if self.has_trait(key):
--> 997                     setattr(self, key, value)
    998                 else:
    999                     # passthrough args that don't set traits to super

~\anaconda3\lib\site-packages\traitlets\traitlets.py in __set__(self, obj, value)
    583             raise TraitError('The "%s" trait is read-only.' % self.name)
    584         else:
--> 585             self.set(obj, value)
    586 
    587     def _validate(self, obj, value):

~\anaconda3\lib\site-packages\traitlets\traitlets.py in set(self, obj, value)
    557 
    558     def set(self, obj, value):
--> 559         new_value = self._validate(obj, value)
    560         try:
    561             old_value = obj._trait_values[self.name]

~\anaconda3\lib\site-packages\traitlets\traitlets.py in _validate(self, obj, value)
    589             return value
    590         if hasattr(self, 'validate'):
--> 591             value = self.validate(obj, value)
    592         if obj._cross_validation_lock is False:
    593             value = self._cross_validate(obj, value)

~\anaconda3\lib\site-packages\traitlets\traitlets.py in validate(self, obj, value)
   1868     def validate(self, obj, value):
   1869         if not isinstance(value, int):
-> 1870             self.error(obj, value)
   1871         return _validate_bounds(self, obj, value)
   1872 

~\anaconda3\lib\site-packages\traitlets\traitlets.py in error(self, obj, value)
    623             e = "The '%s' trait must be %s, but a value of %r was specified." \
    624                 % (self.name, self.info(), repr_type(value))
--> 625         raise TraitError(e)
    626 
    627     def get_metadata(self, key, default=None):

TraitError: The 'scale' trait of a Symbol instance must be an int, but a value of 2335 <class 'numpy.int64'> was specified.

Answer 1

如果您查看 gmaps 的代码，它使用库 traitlets 来确保有效的类型使用。

https://github.com/pbugnion/gmaps/blob/4f75c8301de00fd831449fe685bd209b5f5ee3e3/gmaps/marker.py#L137

具体部分：

...
from traitlets import Unicode, Int, List, observe, HasTraits, Bool
...
scale = Int(
    default_value=4, allow_none=True, min=1
).tag(sync=True)

据我所知，traitlets 不支持 Numpy 类型，因此您需要将其转换回 Python Integer。