Bokeh Select Widget to Update Plot

Question

I am trying to build a grid plot that updates based on value selected from 'Select' widget using Bokeh. The graph works but there is no interaction between the widget and the graph. I am not sure how to do this. The goal is to use the 'Select' to update dfPlot then follow the remaining steps.

Here is what i have so far:

output_file('layout.html')

select = Select(title="Option:", options= list(dfExpense['Ident'].unique()), value= "VALUE")

def update_plot(attr, old, new):
    dfPlot = dfExpense[dfExpense['Ident'] == select.value]

select.on_change('value', update_plot)

d = []

for x in dfPlot['Account'].unique():
    d.append(f's_{x}')

plt = []

for i, x in enumerate(dfPlot['Account'].unique()):
    dftemp = dfPlot[dfPlot['Account']==gl]
    source1 = ColumnDataSource(dftemp)
    d[i] = figure(plot_width = 250, plot_height = 250)
    d[i].circle('X', 'Amount', source = source1)
    plt.append(d[i])
    
grid= gridplot([i for i in plt], ncols = 6)
l = row(grid, select)
show(l)

curdoc().add_root(l)

Thanks!

Answer 1

Someone else will probably give you a better answer. I'll just say, I think you might be doing things completely wrong for what you are trying to do (I did the same thing when starting to work with Bokeh).

My understanding after a bit of experience with Bokeh, as it relates to your problem, is as follows:

• Using curdoc to make an interactive widget based Bokeh plot means you are using Python to interact with the plot, meaning that you must use a Bokeh server, not just use a.html file. (as a corollary, you won't be using show or output file ) https://docs.bokeh.org/en/latest/docs/user_guide/server.html
• You can still make a standalone.html file and make it have interactive widgets like sliders, but you will have to write some Javascript. You'll most likely want to do this by utilizing CustomJS within Bokeh, which makes it relatively easy. https://docs.bokeh.org/en/latest/docs/user_guide/interaction/callbacks.html

I had a similar problem, wanting interactivity without using a Python Bokeh server. CustomJS ended up serving my needs quite well, and even though I'm a novice at Javascript, they make it pretty easy (well, especially if your problem is similar to the examples, it can get tricky otherwise but still not very hard).