# pytudes
"An *étude* (a French word meaning *study*) is an instrumental musical composition, usually short, of considerable difficulty, and designed to provide practice material for perfecting a particular musical skill." — [Wikipedia](https://en.wikipedia.org/wiki/%C3%89tude)
This project contains **pytudes**—Python programs, usually short, for perfecting particular programming skills.
Some programs are in Jupyter (`.ipynb`) notebooks, some in `.py` files. For each notebook you can:
- Click on [c](https://colab.research.google.com) to **run** the notebook on Colab
- Click on [d](https://deepnote.com) to **run** the notebook on DeepNote
- Click on [m](https://mybinder.org) to **run** the notebook on MyBinder
- Click on [n](https://nbviewer.jupyter.org/) to **view** the notebook on NBViewer
- Click on the title to **view** the notebook on github.
- Hover over the title to **view** a description.
# Index of Jupyter (IPython) Notebooks
|Run|Year|Programming Examples|
|---|----|---|
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Advent-2020.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FAdvent-2020.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FAdvent-2020.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Advent-2020.ipynb) | 2020 | Advent of Code 2020 |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Advent-2018.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FAdvent-2018.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FAdvent-2018.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Advent-2018.ipynb) | 2018 | Advent of Code 2018 |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Advent%202017.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FAdvent%202017.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FAdvent%202017.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Advent%202017.ipynb) | 2017 | Advent of Code 2017 |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Advent%20of%20Code.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FAdvent%20of%20Code.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FAdvent%20of%20Code.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Advent%20of%20Code.ipynb) | 2016 | Advent of Code 2016 |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Beal.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FBeal.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FBeal.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Beal.ipynb) | 2018 | Beal's Conjecture Revisited |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Bike%20Speed%20versus%20Grade.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FBike%20Speed%20versus%20Grade.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FBike%20Speed%20versus%20Grade.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Bike%20Speed%20versus%20Grade.ipynb) | 2020 | Bicycling Statistics |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Cant-Stop.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FCant-Stop.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FCant-Stop.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Cant-Stop.ipynb) | 2018 | Can't Stop |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Sierpinski.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FSierpinski.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FSierpinski.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Sierpinski.ipynb) | 2019 | Chaos with Triangles |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Life.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FLife.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FLife.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Life.ipynb) | 2017 | Conway's Game of Life |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Maze.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FMaze.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FMaze.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Maze.ipynb) | 2020 | Generating and Solving Mazes |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/PhotoFocalLengths.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FPhotoFocalLengths.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FPhotoFocalLengths.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/PhotoFocalLengths.ipynb) | 2020 | Photo Focal Lengths |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Pickleball.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FPickleball.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FPickleball.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Pickleball.ipynb) | 2018 | Pickleball Tournament |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Project%20Euler%20Utils.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FProject%20Euler%20Utils.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FProject%20Euler%20Utils.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Project%20Euler%20Utils.ipynb) | 2017 | Project Euler Utilities |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Electoral%20Votes.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FElectoral%20Votes.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FElectoral%20Votes.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Electoral%20Votes.ipynb) | 2020 | Tracking Trump: Electoral Votes |
|Run|Year|Logic and Number Puzzles|
|---|----|---|
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Cryptarithmetic.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FCryptarithmetic.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FCryptarithmetic.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Cryptarithmetic.ipynb) | 2014 | Cryptarithmetic |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Euler's%20Conjecture.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FEuler's%20Conjecture.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FEuler's%20Conjecture.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Euler's%20Conjecture.ipynb) | 2018 | Euler's Sum of Powers Conjecture |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Countdown.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FCountdown.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FCountdown.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Countdown.ipynb) | 2020 | Four 4s, Five 5s, and Countdowns |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Socks.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FSocks.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FSocks.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Socks.ipynb) | 2019 | Pairing Socks |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Sicherman%20Dice.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FSicherman%20Dice.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FSicherman%20Dice.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Sicherman%20Dice.ipynb) | 2018 | Sicherman Dice |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Golomb-Puzzle.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FGolomb-Puzzle.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FGolomb-Puzzle.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Golomb-Puzzle.ipynb) | 2014 | Sol Golomb's Rectangle Puzzle |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/SquareSum.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FSquareSum.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FSquareSum.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/SquareSum.ipynb) | 2020 | Square Sum Puzzle |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Cheryl.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FCheryl.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FCheryl.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Cheryl.ipynb) | 2020 | When is Cheryl's Birthday? (new: Mad Cheryl) |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Cheryl-and-Eve.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FCheryl-and-Eve.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FCheryl-and-Eve.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Cheryl-and-Eve.ipynb) | 2015 | When Cheryl Met Eve: A Birthday Story |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/xkcd1313.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2Fxkcd1313.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2Fxkcd1313.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/xkcd1313.ipynb) | 2015 | xkcd 1313: Regex Golf |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/xkcd1313-part2.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2Fxkcd1313-part2.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2Fxkcd1313-part2.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/xkcd1313-part2.ipynb) | 2015 | xkcd 1313: Regex Golf (Part 2: Infinite Problems) |
|Run|Year|The Riddler (from 538)|
|---|----|---|
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Riddler%20Battle%20Royale.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FRiddler%20Battle%20Royale.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FRiddler%20Battle%20Royale.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Riddler%20Battle%20Royale.ipynb) | 2017 | Battle Royale |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/CrossProduct.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FCrossProduct.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FCrossProduct.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/CrossProduct.ipynb) | 2021 | CrossProduct |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/flipping.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2Fflipping.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2Fflipping.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/flipping.ipynb) | 2020 | Flipping Cards; A Guessing Game |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/RiddlerLottery.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FRiddlerLottery.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FRiddlerLottery.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/RiddlerLottery.ipynb) | 2019 | Lottery |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/NightKing.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FNightKing.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FNightKing.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/NightKing.ipynb) | 2019 | How Many Soldiers to Beat the Night King? |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Mean%20Misanthrope%20Density.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FMean%20Misanthrope%20Density.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FMean%20Misanthrope%20Density.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Mean%20Misanthrope%20Density.ipynb) | 2017 | Misanthropic Neighbors |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Orderable%20Cards.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FOrderable%20Cards.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FOrderable%20Cards.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Orderable%20Cards.ipynb) | 2018 | Properly Ordered Card Hands |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/TourDe538.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FTourDe538.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FTourDe538.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/TourDe538.ipynb) | 2020 | Tour de 538 |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/TwelveBalls.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FTwelveBalls.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FTwelveBalls.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/TwelveBalls.ipynb) | 2020 | Weighing Twelve Balls |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/war.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2Fwar.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2Fwar.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/war.ipynb) | 2020 | War. What is it Good For? |
|Run|Year|Word Puzzles|
|---|----|---|
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Boggle.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FBoggle.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FBoggle.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Boggle.ipynb) | 2020 | Boggle / Inverse Boggle |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/ElementSpelling.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FElementSpelling.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FElementSpelling.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/ElementSpelling.ipynb) | 2020 | Chemical Element Spelling |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/equilength-numbers.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2Fequilength-numbers.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2Fequilength-numbers.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/equilength-numbers.ipynb) | 2020 | Equilength Numbers: FOUR = 4 |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Gesture%20Typing.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FGesture%20Typing.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FGesture%20Typing.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Gesture%20Typing.ipynb) | 2017 | Gesture Typing |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Ghost.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FGhost.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FGhost.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Ghost.ipynb) | 2017 | Ghost: A Word game |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/How%20to%20Do%20Things%20with%20Words.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FHow%20to%20Do%20Things%20with%20Words.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FHow%20to%20Do%20Things%20with%20Words.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/How%20to%20Do%20Things%20with%20Words.ipynb) | 2018 | How to Do Things with Words: NLP in Python |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/jotto.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2Fjotto.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2Fjotto.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/jotto.ipynb) | 2020 | Jotto: A Word Guessing Game |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Fred%20Buns.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FFred%20Buns.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FFred%20Buns.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Fred%20Buns.ipynb) | 2015 | Let's Code About Bike Locks |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Scrabble.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FScrabble.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FScrabble.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Scrabble.ipynb) | 2017 | Scrabble: Refactoring a Crossword Game Program |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/SpellingBee.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FSpellingBee.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FSpellingBee.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/SpellingBee.ipynb) | 2020 | Spelling Bee |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/PropositionalLogic.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FPropositionalLogic.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FPropositionalLogic.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/PropositionalLogic.ipynb) | 2017 | Translating English into Propositional Logic |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/pal3.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2Fpal3.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2Fpal3.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/pal3.ipynb) | 2017 | World's Longest Palindrome |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Portmantout.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FPortmantout.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FPortmantout.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Portmantout.ipynb) | 2020 | World's Shortest Portmantout Word |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/xkcd-Name-Dominoes.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2Fxkcd-Name-Dominoes.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2Fxkcd-Name-Dominoes.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/xkcd-Name-Dominoes.ipynb) | 2018 | xkcd 1970: Name Dominoes |
|Run|Year|Probability and Uncertainty|
|---|----|---|
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Probability.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FProbability.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FProbability.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Probability.ipynb) | 2018 | A Concrete Introduction to Probability |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/ProbabilityParadox.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FProbabilityParadox.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FProbabilityParadox.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/ProbabilityParadox.ipynb) | 2016 | Probability, Paradox, and the Reasonable Person Principle |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/ProbabilitySimulation.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FProbabilitySimulation.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FProbabilitySimulation.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/ProbabilitySimulation.ipynb) | 2020 | Estimating Probabilities with Simulations |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Coin%20Flip.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FCoin%20Flip.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FCoin%20Flip.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Coin%20Flip.ipynb) | 2019 | The Devil and the Coin Flip Game |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Dice%20Baseball.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FDice%20Baseball.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FDice%20Baseball.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Dice%20Baseball.ipynb) | 2020 | Dice Baseball |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Economics.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FEconomics.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FEconomics.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Economics.ipynb) | 2018 | Economics Simulation |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/poker.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2Fpoker.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2Fpoker.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/poker.ipynb) | 2012 | Poker Hand Ranking |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/risk.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2Frisk.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2Frisk.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/risk.ipynb) | 2020 | The Unfinished Game .... of Risk |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/WWW.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FWWW.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FWWW.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/WWW.ipynb) | 2019 | WWW: Who Will Win (NBA Title)? |
|Run|Year|Computer Science Algorithms and Concepts|
|---|----|---|
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Snobol.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FSnobol.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FSnobol.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Snobol.ipynb) | 2017 | Bad Grade, Good Experience |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/BASIC.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FBASIC.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FBASIC.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/BASIC.ipynb) | 2017 | BASIC Interpreter |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Convex%20Hull.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FConvex%20Hull.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FConvex%20Hull.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Convex%20Hull.ipynb) | 2017 | Convex Hull Problem |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/How%20To%20Count%20Things.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FHow%20To%20Count%20Things.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FHow%20To%20Count%20Things.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/How%20To%20Count%20Things.ipynb) | 2020 | How to Count Things |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/StableMatching.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FStableMatching.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FStableMatching.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/StableMatching.ipynb) | 2020 | Stable Matching Problem |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/Differentiation.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FDifferentiation.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FDifferentiation.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/Differentiation.ipynb) | 2017 | Symbolic Algebra, Simplification, and Differentiation |
| [c](https://colab.research.google.com/github/norvig/pytudes/blob/master/ipynb/TSP.ipynb) [d](https://beta.deepnote.org/launch?template=python_3.6&url=https%3A%2F%2Fgithub.com%2Fnorvig%2Fpytudes%2Fblob%2Fmaster%2Fipynb%2FTSP.ipynb) [m](https://mybinder.org/v2/gh/norvig/pytudes/master?filepath=ipynb%2FTSP.ipynb) [n](https://nbviewer.jupyter.org/github/norvig/pytudes/blob/master/ipynb/TSP.ipynb) | 2018 | Traveling Salesperson Problem |
# Index of Python Files
| File | Description | Documentation |
|:--|:----|----|
|[beal.py](/blob/master/py/beal.py)|*Search for counterexamples to Beal's Conjecture*|[documentation](http://norvig.com/beal.html)|
|[docex.py](/blob/master/py/docex.py)|*An obsolete framework for running unit tests, similar to `doctest`*||
|[ibol.py](/blob/master/py/ibol.py)|*An Exercise in Species Barcoding*|[documentation](http://norvig.com/ibol.html)|
|[lettercount.py](/blob/master/py/lettercount.py)|*Convert Google Ngram Counts to Letter Counts*|[documentation](http://norvig.com/mayzner.html)|
|[lis.py](/blob/master/py/lis.py)|*Lisp Interpreter written in Python*|[documentation](http://norvig.com/lispy.html)|
|[lispy.py](/blob/master/py/lispy.py)|*Even Better Lisp Interpreter written in Python*|[documentation](http://norvig.com/lispy2.html)|
|[lispytest.py](/blob/master/py/lispytest.py)|*Tests for Lisp Interpreters*||
|[pal.py](/blob/master/py/pal.py)|*Find long palindromes*|[documentation](http://norvig.com/palindrome.html)|
|[pal2.py](/blob/master/py/pal2.py)|*Find longer palindromes*|[documentation](http://norvig.com/palindrome.html)|
|[pal3.py](/blob/master/py/pal3.py)|*Find even longer palindromes*|[documentation](http://norvig.com/palindrome.html)|
|[pytudes.py](/blob/master/py/pytudes.py)|*Pre-process text to generate this README.md file.*||
|[py2html.py](/blob/master/py/py2html.py)|*Pretty-printer to format Python files as html*||
|[SET.py](/blob/master/py/SET.py)|*Analyze the card game SET*|[documentation](http://norvig.com/SET.html)|
|[spell.py](/blob/master/py/spell.py)|*Spelling corrector*|[documentation](http://norvig.com/spell-correct.html)|
|[sudoku.py](/blob/master/py/sudoku.py)|*Program to solve sudoku puzzles*|[documentation](http://norvig.com/sudoku.html)|
|[testaccum.py](/blob/master/py/testaccum.py)|*Tests for my failed Python `accumulation display` proposal*|[documentation](http://norvig.com/pyacc.html)|
|[yaptu.py](/blob/master/py/yaptu.py)|*Yet Another Python Templating Utility*||
# Etudes for Programmers
I got the idea for the *"etudes"* part of the name from
this [1978 book](https://books.google.com/books/about/Etudes_for_programmers.html?id=u89WAAAAMAAJ)
by [Charles Wetherell](http://demin.ws/blog/english/2012/08/25/interview-with-charles-wetherell)
that was very influential to me when I was first learning to program. I still have my copy.
