Blank plot with panel

Dear community,
as you can see in the picture (datfarme) I want to plot a time series plot (for total vaccinations per date ) with a check box filter for the countries (i have 60 country in my dataset ) but all i get is a blank plot.
This is my code :
import panel as pn
import altair as alt
from altair import datum
import pandas as pd
from vega_datasets import data
import datetime as dt

df2 = df.copy()

create list of company names (tickers) to use as options

tickers = [‘Argentina’, ‘Austria’, ‘Bahrain’, ‘Belgium’ ,‘Brazil’, ‘Bulgaria’ ,‘Canada’,
‘Chile’ ,‘China’ ,‘Costa0Rica’ ,‘Croatia’ ,‘Cyprus’, ‘Czechia’, ‘Denmark’,
‘Ecuador’, ‘England’ ,‘Estonia’ ,‘Finland’, ‘France’ ,‘Germany’, ‘Gibraltar’,
‘Greece’ ,‘Hungary’, ‘Iceland’, ‘India’, ‘Indonesia’ ,‘Ireland’ ,‘Isle0of0Man’,
‘Israel’ ,‘Italy’ ,‘Kuwait’ ,‘Latvia’ ,‘Lithuania’ ,‘Luxembourg’ ,‘Malta’,
‘Mexico’, ‘Netherlands’, ‘Northern0Ireland’ ,‘Norway’ ,‘Oman’ ,‘Panama’,
‘Poland’ ,‘Portugal’, ‘Romania’, ‘Russia’ ,‘Saudi0Arabia’ ,‘Scotland’ ,‘Serbia’,
‘Seychelles’, ‘Singapore’ ,‘Slovakia’, ‘Slovenia’ ,‘Spain’ ,‘Sweden’,
‘Switzerland’ ,‘Turkey’ ,‘United0Arab0Emirates’ ,‘United0Kingdom’,
‘United0States’, ‘Wales’]

this creates the dropdown widget

ticker = pn.widgets.Select(name=‘country’, options=tickers)

this creates the date range slider

date_range_slider = pn.widgets.DateRangeSlider(
name=‘Date Range Slider’,
start=dt.datetime(2020, 12, 13), end=dt.datetime(2021, 1, 25),
value=(dt.datetime(2020, 12, 13), dt.datetime(2021, 1, 25))

title = ‘total vaccinations per day’
subtitle = ‘This dashboard allows you to select a country and date range to see total vaccinations per day.’

@pn.depends(ticker.param.value, date_range_slider.param.value)

def get_plot(ticker, date_range):
# Load and format the data
df = df2 # define df
df[‘date’] = pd.to_datetime(df[‘date’])
# create date filter using values from the range slider
# store the first and last date range slider value in a var
start_date = date_range_slider.value[0]
end_date = date_range_slider.value[1]
# create filter mask for the dataframe
mask = (df[‘date’] > start_date) & (df[‘date’] <= end_date)
df = df.loc[mask] # filter the dataframe
# create the Altair chart object
chart = alt.Chart(df).mark_line().encode( alt.X(‘date’),alt.Y(‘total_vaccinations’),
(datum.symbol == ticker) # this ties in the filter
return chart

dashboard = pn.Row(pn.Column(title, subtitle, ticker, date_range_slider),
get_plot # our draw chart function!

any help would be appreciated and thank you in advance

Hi @Yassine_Haouas Please edit your post to use code formatting so that the code is intelligible (either with the </> icon on the editing toolbar, or triple backtick ``` fences around the code blocks)

However, I should also add that the above code does not use Bokeh directly anywhere. If that’s correct, then this is not the appropriate forum for your question.

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Hi @Bryan thank you for responding. Well i was asked to do this task using bokeh but i didn’t to do it so i used panel. is there any way to do the same work with bokeh?

@Yassine_Haouas There are lots of examples of content with widgets that filter data or update plots in the docs and in the examples repo. The question is too vague to offer any specific advice.

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