jupytext	kernelspec
cell_metadata_filter formats notebook_metadata_filter text_representation all,-hidden,-heading_collapsed md:myst all,-language_info,-toc,-jupytext.text_representation.jupytext_version,-jupytext.text_representation.format_version extension format_name .md myst	display_name language name Python 3 python python3

Licence CC BY-NC-ND - Thierry Parmentelat

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Embedding pythontutor.com illustrations in Jupyter

this notebook is stored in text (markdown) format using jupytext, make sure to have this tool installed if you want to open it locally

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Installation

$ pip3 install ipythontutor

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Screeshot

As github won't render iframes embedded in a ipynb, here's a screenshot

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Basic Usage

# required to load the extension
%load_ext ipythontutor

In its simplest form, the code in the cell is handed over (as python3) to the excellent http://pythontutor.com/

%%ipythontutor
original = reference = [1, 2]
original[0] = 'boom'
print(reference)

Setting sizes

%%ipythontutor height=400 width=850
def fact(n):
    return 1 if n <= 1 else n * fact(n-1)
original = [fact(3), fact(4)]
reference = original[:]
original[0] = 'boom'
print(reference)

Scaling

If your page is smaller than what pythontutor can reasonably work with, you can specify a scaling ratio.

%%ipythontutor width=600 height=200 ratio=0.7
import copy
original = [1, [2, 3]]
reference = copy.deepcopy(original)
original[1][0] = 'boom'
print(reference)

Add a button to open pythontutor in a new tab

%%ipythontutor linkButton=true
def fact(n):
    return 1 if n <= 1 else n * fact(n-1)
original = [fact(3), fact(4)]
reference = original[:]
original[0] = 'boom'
print(reference)

Other settings

The following list shows the settings that can be tweaked on the magic line. See also this page about embedding pythontutor for more details on these settings:

from ipythontutor import Magics
for var, default in Magics.defaults.items():
    print(f"{var:>20} - defaults to - {default:<}")

Note on proto

The default is to use https to reach pythontutor, as this is exepcted to work in most cases. If that's not working for you, instead of setting proto=http on each magic cell, you can change this globally - like any other default btw - this way:

from ipythontutor import Magics
Magics.defaults['proto'] = 'http'

Using python2

%%ipythontutor py=2
print "Hey"
original = [1, 2]
copy = original[:]
original[0] = 'boom'

See also

Check out another pure approach, that does not rely on pythontutor, at the nbtutor project.