Plotting a Pie Chart using Bokeh Library in Python

To plot a pie chart using the Bokeh library in Python, follow these steps:

1. Install the Bokeh library if you haven’t already:

   pip install bokeh

2. Import the necessary modules from Bokeh:

   from bokeh.plotting import figure, show
   from bokeh.io import output_file
   from bokeh.transform import factor_cmap
   import pandas as pd

3. Prepare your data. For this example, we’ll use a simple dictionary:

   data = {'A': 20, 'B': 15, 'C': 30, 'D': 35}

4. Convert the data into a format suitable for Bokeh:

   data_df = pd.DataFrame(list(data.items()), columns=['Category', 'Value'])

5. Set up the output file and plot the pie chart:

   # Set up the output file
   output_file('pie_chart.html')
   
   # Create a pie chart
   p = figure(height=350, title="Pie Chart", toolbar_location=None, tools="hover", tooltips="@Category: @Value", x_range=(-0.5, 1.0))
   
   # Add a wedge renderer
   p.wedge(x=0, y=1, radius=0.4,
           start_angle='start_angle', end_angle='end_angle',
           line_color='white', fill_color='color', legend_field='Category',
           source=data_df)
   
   # Show the plot
   show(p)

This code creates a pie chart and saves it as ‘pie_chart.html’. You can open this file in a web browser to view the chart.