Jupyter Tidbit: Display handles
November 03, 2018
This post originates from a gist that supports comments, forks, and execution in binder.
Summary¶
IPython's display() function can return a DisplayHandle object. You can use a DisplayHandle to update the output of one cell from any other cell in a Jupyter Notebook.
Example¶
The display_handle.ipynb notebook below calls display(display_id=True) to get a display handle instance. It then uses the DisplayHandle.display method to show some initial, static Markdown. Later, in a different cell, it calls DisplayHandle.update in a loop to show a range of emoji characters.
Why is this useful?¶
You can use display handles to redraw matplotlib plots, re-render DataFrame tables, print log file updates, etc. from code executed anywhere in the notebook.
display_handle.ipynb
import itertools
import time
from IPython.display import Markdown
Make a display handle.
dh = display(display_id=True)
Show some Markdown (or plain text, or a plot, or ...)
display(Markdown('# Display Update Fun'))
dh.display(Markdown(''))
Update the display above.
for i in itertools.cycle(range(0x1F600, 0x1F650)):
dh.update(Markdown(f'## &#{i}; {hex(i)}'))
time.sleep(0.5)