滑块值未更新Bokeh Python

Question

我正在努力通过使用Bokeh在Jupyter Notebook中进行交互式绘图。我想绘制一张世界地图，并显示一些数据随时间的变化。我成功制作了一个图并使用了滑块来调整年份，但是当我更改滑块时，滑块值将不会更新。滑块的代码如下：

#creating the data source as a dict
source = ColumnDataSource({
    'x': p_df['x'], 
    'y': p_df['y'], 
    'Country': p_df['Country'], 
    'nkill': p_df['nkill']
})

#making a slider and assign the update_plot function to changes
slider = Slider(start=start_yr, end=end_yr, step=1, value=start_yr, title='Year')
slider.on_change('value',update_plot)

#the update_plot function which needs to run based on the new slider.value
def update_plot(attr, old, new):
    #Update glyph locations
    yr = slider.value
    Amountkills_dt_year = p_df[p_df['Year'] ==yr]
    new_data = {
        'x': Amountkills_dt_year['x'], 
        'y': Amountkills_dt_year['y'], 
        'Country': Amountkills_dt_year['Country'], 
        'nkill': Amountkills_dt_year['nkill']
    }
    source.data = new_data
    #Update colors
    color_mapper = LinearColorMapper(palette='Viridis256',
                                 low = min(Amount_of_Terrorist_Attacks['nkill']),
                                 high = max(Amount_of_Terrorist_Attacks['nkill']))

我想使用update_plot（）函数更新绘图的位置。我尝试了Python bokeh slider not refreshing plot中的解决方案，但仍然遇到了同样的错误。

Answer 1

散景小部件（如滑块）在jupyter笔记本中不起作用（至少，并非不使用某些javascript）。正如documentation所说：

To use widgets, you must add them to your document and define their functionality. Widgets can be added directly to the document root or nested inside a layout. There are two ways to program a widget’s functionality:

        Use the CustomJS callback (see JavaScript Callbacks). This will work in standalone HTML documents.

        Use bokeh serve to start the Bokeh server and set up event handlers with .on_change (or for some widgets, .on_click).

作为@bigreddot的提示，您将需要使用bokeh服务器，否则here中讨论的Jupyter交互器讨论中的某些功能。