python bokeh plotting package does not cache plots in jupyter notebook

Question

Been running into a frustrating problem with the bokeh plotting package in python. So I have a jupyter notebook (notebook version 5.0.0) in which I have some bokeh plots. The notebook is pretty large now, so it does take a bit of time to load. Anyhow, when I was using Matplotlib the images in the notebook would be cached. That way I would not need to rerun them each time I ran the notebook.

Bokeh has the same ability to cache the images, but I cannot seem to get the image cache to work. So for a very simple example, if I had the following code in a notebook:

from bokeh.resources import INLINE
import builtins
import os, sys
import time
import pyugend
import datetime
from IPython.lib import deepreload
builtins.reload = deepreload.reload
from ipywidgets import widgets
from IPython.display import display
from bokeh.io import show, output_notebook
from bokeh.layouts import gridplot
from bokeh.palettes import Viridis3
from bokeh.plotting import figure
from bokeh.charts import defaults
from bokeh import mpl
defaults.width = 700
defaults.height = 700

output_notebook(resources=INLINE)
#output_notebook()
#notebook_handle=True
%reload_ext autoreload
time.sleep(1)

from bokeh.sampledata.iris import flowers

colormap = {'setosa': 'red', 'versicolor': 'green', 'virginica': 'blue'}
colors = [colormap[x] for x in flowers['species']]

p = figure(title = "Iris Morphology")
p.xaxis.axis_label = 'Petal Length'
p.yaxis.axis_label = 'Petal Width'

p.circle(flowers["petal_length"], flowers["petal_width"],
         color=colors, fill_alpha=0.2, size=10)


show(p)

Running this plot works just fine. But when I saved the notebook, closed it, and reopened it, the plot would not show up again.

Anyone else have this issue.

Answer 1

I figured out the answer to this question. So the problem was with the Jupyter initialization cells extension. I had the code to do the imports of bokeh in the initialization cells at the bottom of my notebook. But when I did this for some reason the plotting cells that were earlier in the notebook were not displaying the cached images.

So I had to basically put the imports of the initialization cells at the very beginning of the notebook. Only then did the caching of images work. Interesting problem.