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"id": "01a08217-3e96-7288-b82b-331725d8fac1", "title": "Opening Windows files from bash and eshell", "url": "https://www.johndcook.com/blog/2020/10/17/windows-files-from-eshell/", "published_at": "2020-10-17T15:06:10+00:00" }, { "id": "01a08217-3e96-7288-b82b-33173b0aff21", "title": "Searching Greek and Hebrew with regular expressions", "url": "https://www.johndcook.com/blog/2020/09/20/unicode-regex/", "published_at": "2020-09-20T21:13:38+00:00" }, { "id": "01a08217-3e96-7288-b82b-33173b94ab06", "title": "Descartes and Toolz", "url": "https://www.johndcook.com/blog/2020/09/20/descartes-and-toolz/", "published_at": "2020-09-20T15:22:47+00:00" }, { "id": "01a08217-3e96-7288-b82b-33172628c204", "title": "Org entities", "url": "https://www.johndcook.com/blog/2020/08/28/org-entities/", "published_at": "2020-08-28T14:03:31+00:00" }, { "id": "01a08217-3e96-7288-b82b-331726fcc21e", "title": "Entering symbols in Emacs", "url": "https://www.johndcook.com/blog/2020/08/18/emacs-symbols/", "published_at": "2020-08-18T12:21:29+00:00" }, { "id": "01a08217-3e96-7288-b82b-33173bfb6b04", "title": "Time spent on the moon", "url": "https://www.johndcook.com/blog/2020/08/01/time-spent-on-the-moon/", "published_at": "2020-08-01T20:46:48+00:00" }, { "id": "01a08217-3e96-7288-b82b-33173c3c2984", "title": "A spring, a rubber band, and chaos", "url": "https://www.johndcook.com/blog/2020/04/26/spring-rubberband-chaos/", "published_at": "2020-04-26T12:39:36+00:00" }, { "id": "01a08217-3e96-7288-b82b-33173c755bc0", "title": "More efficient way to sum a list comprehension", "url": "https://www.johndcook.com/blog/2020/01/15/generator-expression/", "published_at": "2020-01-15T16:17:16+00:00" }, { "id": "01a08217-3e96-7288-b82b-33173c7e6cf3", "title": "Area of sinc and jinc function lobes", "url": "https://www.johndcook.com/blog/2019/12/31/sinc-jinc-lobes/", "published_at": "2019-12-31T15:23:05+00:00" }, { "id": "01a08217-3e96-7288-b82b-33173cbf87d0", "title": "Minimizing context switching between shell and Python", "url": "https://www.johndcook.com/blog/2019/12/30/shell-and-python/", "published_at": "2019-12-30T14:05:25+00:00" }, { "id": "01a08217-3e96-7288-b82b-33173cf74191", "title": "Calculating the period of Van der Pol oscillators", "url": "https://www.johndcook.com/blog/2019/12/26/van-der-pol-period/", "published_at": "2019-12-26T12:35:10+00:00" }, { "id": "01a08217-3e96-7288-b82b-33173d3b2280", "title": "Solving Van der Pol equation with ivp_solve", "url": "https://www.johndcook.com/blog/2019/12/22/van-der-pol/", "published_at": "2019-12-22T23:57:16+00:00" }, { "id": "01a08217-3e96-7288-b82b-33173d5372ac", "title": "Data Science and Star Science", "url": "https://www.johndcook.com/blog/2019/11/30/data-science-and-star-science/", "published_at": "2019-12-01T04:11:53+00:00" }, { "id": "01a08217-3e96-7288-b82b-33173db87f62", "title": "Generating Python code from SymPy", "url": "https://www.johndcook.com/blog/2019/10/31/generating-python-code-from-sympy/", "published_at": "2019-10-31T15:18:08+00:00" }, { "id": "01a08217-3e96-7288-b82b-33172796154e", "title": "Control characters", "url": "https://www.johndcook.com/blog/2019/09/28/control-characters/", "published_at": "2019-09-28T14:53:05+00:00" }, { "id": "01a08217-3e96-7288-b82b-331727b70168", "title": "Journalistic stunt with Emacs", "url": "https://www.johndcook.com/blog/2019/07/03/journalistic-stunt-with-emacs/", "published_at": "2019-07-03T13:47:28+00:00" }, { "id": "01a08217-3e96-7288-b82b-33173df6f247", "title": "Calling Python from Mathematica", "url": "https://www.johndcook.com/blog/2019/04/18/calling-python-from-mathematica/", "published_at": "2019-04-19T00:42:21+00:00" }, { "id": "01a08217-3e96-7288-b82b-33173ed130c6", "title": "Squircle perimeter and the isoparametric problem", "url": "https://www.johndcook.com/blog/2019/04/11/dido-problem/", "published_at": "2019-04-11T11:25:40+00:00" }, { "id": "01a08217-3e96-7288-b82b-331728653f16", "title": "Emacs features that use regular expressions", "url": "https://www.johndcook.com/blog/2018/01/27/emacs-features-that-use-regular-expressions/", "published_at": "2018-01-27T17:10:31+00:00" }, { "id": "01a08217-3e96-7288-b82b-3317293f9e3f", "title": "Selecting things in Emacs", "url": "https://www.johndcook.com/blog/2017/08/09/selecting-things-in-emacs/", "published_at": "2017-08-09T16:27:07+00:00" }, { "id": "01a08217-3e96-7288-b82b-3317294e79bb", "title": "Setting up Emacs shell on a Mac", "url": "https://www.johndcook.com/blog/2016/11/30/setting-up-emacs-shell-on-a-mac/", "published_at": "2016-11-30T14:05:11+00:00" }, { "id": "01a08217-3e96-7288-b82b-331729bc7af4", "title": "Five lemma, ASCII art, and Unicode", "url": "https://www.johndcook.com/blog/2016/06/21/five-lemma-ascii-art-and-unicode/", "published_at": "2016-06-21T18:20:35+00:00" }, { "id": "01a08217-3e96-7288-b82b-33172abb5435", "title": "ASCII art diagrams in Emacs org-mode", "url": "https://www.johndcook.com/blog/2016/06/15/ascii-art-diagrams-in-emacs-org-mode/", "published_at": "2016-06-15T15:19:10+00:00" }, { "id": "01a08217-3e96-7288-b82b-33172b88a4f3", "title": "Rare letter combinations and key chords", "url": "https://www.johndcook.com/blog/2015/02/01/rare-bigrams/", "published_at": "2015-02-01T20:44:04+00:00" }, { "id": "01a08217-3e96-7288-b82b-33172c3ac189", "title": "Managing Emacs windows", "url": "https://www.johndcook.com/blog/2015/01/26/managing-emacs-windows/", "published_at": "2015-01-26T23:27:05+00:00" }, { "id": "01a08217-3e96-7288-b82b-33172cae3fc1", "title": "Emacs resources", "url": "https://www.johndcook.com/blog/2014/11/26/emacs-resources/", "published_at": "2014-11-26T12:16:43+00:00" }, { "id": "01a08217-3e96-7288-b82b-33172d61b5e0", "title": "Interview with Sacha Chua", "url": "https://www.johndcook.com/blog/2013/03/19/interview-with-sacha-chua/", "published_at": "2013-03-19T12:00:27+00:00" } ] posts Claim your blog

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John D. Cook

johndcook.com

2026

Servers in dawn-dusk orbit original ↗

25 Sept 2026

Navigation with only addition, subtraction, and tables original ↗

23 Sept 2026

Nathaniel Bowditch original ↗

22 Sept 2026

Haversine law original ↗

21 Sept 2026

Why fitting a logistic is nearly impossible from early data original ↗

19 Sept 2026

Empirical fractal original ↗

17 Sept 2026

Phone words original ↗

17 Sept 2026

Converting between cosine similarity and concentration ratio original ↗

16 Sept 2026

Coffee + milk ≠ latte original ↗

16 Sept 2026

Fibonacci product original ↗

16 Sept 2026

Simple approximation for spherical cap area original ↗

15 Sept 2026

What counts as a large cosine similarity?original ↗

15 Sept 2026

Guessing the meaning of a number original ↗

14 Sept 2026

Bayesian OCR original ↗

10 Sept 2026

A 50-year-old computer-assisted proof original ↗

9 Sept 2026

AI is an intelligence multiplier original ↗

9 Sept 2026

The part of Navier-Stokes no one is talking about original ↗

9 Sept 2026

Navier-Stokes in the news original ↗

8 Sept 2026

Ngram error rate original ↗

7 Sept 2026

Proof of the rank-trace theorem original ↗

5 Sept 2026

Computing a lower bound on matrix rank original ↗

4 Sept 2026

Hugging Face Easter Egg original ↗

3 Sept 2026

New RSA number factored original ↗

3 Sept 2026

Patented application of linear algebra original ↗

31 Aug 2026

Making the unnecessary easier original ↗

28 Aug 2026

Second solutions original ↗

27 Aug 2026

What is the quality of software that AI writes?original ↗

26 Aug 2026

Junk solutions original ↗

26 Aug 2026

Ultraspherical original ↗

26 Aug 2026

Numerical (in)stability of recurrence relations original ↗

25 Aug 2026

Three-term recurrences original ↗

24 Aug 2026

The von Mises-Fisher distribution original ↗

24 Aug 2026

What exactly is modified about a modified Bessel function?original ↗

23 Aug 2026

Why special function terminology is arcane original ↗

23 Aug 2026

The difference orbit inclination makes original ↗

23 Aug 2026

Coming soon original ↗

22 Aug 2026

How would you know whether an ancient culture had zero?original ↗

21 Aug 2026

AI-generated ASCII diagrams original ↗

20 Aug 2026

Big little hexagon original ↗

19 Aug 2026

The imbalance theorem original ↗

18 Aug 2026

Mean distance to the sun original ↗

18 Aug 2026

Proportion of 1s in a Hadamard matrix original ↗

17 Aug 2026

Probability of correcting errors original ↗

15 Aug 2026

Compressing a Hadamard matrix original ↗

15 Aug 2026

Hadamard Codes and Sphere Packing original ↗

14 Aug 2026

How NASA’s Mariner 9 probe encoded images original ↗

13 Aug 2026

Constructing Hadamard matrices original ↗

13 Aug 2026

Cryptic but consistent original ↗

12 Aug 2026

Linklog | Accurately computing sample variance online original ↗

2 Jan 2026

2025

Converting very long strings to integers in Python original ↗

15 Aug 2025

Monero’s elliptic curve original ↗

27 Jul 2025

Converting between quaternions and rotation matrices original ↗

7 May 2025

2024

How hard is constraint programming?original ↗

31 Oct 2024

2023

Factored random numbers original ↗

18 Nov 2023

Python code for means original ↗

11 Oct 2023

Navigating a LaTeX file original ↗

23 Sept 2023

Searching for proper nouns original ↗

17 Jul 2023

Golden integration original ↗

29 Apr 2023

Good autocomplete original ↗

30 Jan 2023

2022

Python code to solve Kepler’s equation original ↗

2 Nov 2022

Literate programming to reduce errors original ↗

6 Sept 2022

Dump a pickle file to a readable text file original ↗

16 Aug 2022

Keeping data and code together with org-mode original ↗

15 Aug 2022

Naming probability functions original ↗

5 Aug 2022

Inline computed content in org-mode original ↗

3 Aug 2022

Org-mode as a lightweight notebook original ↗

2 Aug 2022

Find log normal parameters for given mean and variance original ↗

25 Feb 2022

2021

Deleting reproducible files in Emacs dired original ↗

12 Dec 2021

Spaceship operator in Python original ↗

12 Apr 2021

Illustrating Gershgorin disks with NumPy original ↗

14 Mar 2021

Pareto and Pandas original ↗

11 Mar 2021

Broadcasting and functors original ↗

10 Mar 2021

Python triple quote strings and regular expressions original ↗

30 Jan 2021

2020

Opening Windows files from bash and eshell original ↗

17 Oct 2020

Searching Greek and Hebrew with regular expressions original ↗

20 Sept 2020

Descartes and Toolz original ↗

20 Sept 2020

Org entities original ↗

28 Aug 2020

Entering symbols in Emacs original ↗

18 Aug 2020

Time spent on the moon original ↗

1 Aug 2020

A spring, a rubber band, and chaos original ↗

26 Apr 2020

More efficient way to sum a list comprehension original ↗

15 Jan 2020

2019

Area of sinc and jinc function lobes original ↗

31 Dec 2019

Minimizing context switching between shell and Python original ↗

30 Dec 2019

Calculating the period of Van der Pol oscillators original ↗

26 Dec 2019

Solving Van der Pol equation with ivp_solve original ↗

22 Dec 2019

Data Science and Star Science original ↗

1 Dec 2019

Generating Python code from SymPy original ↗

31 Oct 2019

Control characters original ↗

28 Sept 2019

Journalistic stunt with Emacs original ↗

3 Jul 2019

Calling Python from Mathematica original ↗

19 Apr 2019

Squircle perimeter and the isoparametric problem original ↗

11 Apr 2019

2018

Emacs features that use regular expressions original ↗

27 Jan 2018

2017

Selecting things in Emacs original ↗

9 Aug 2017

2016

Setting up Emacs shell on a Mac original ↗

30 Nov 2016

Five lemma, ASCII art, and Unicode original ↗

21 Jun 2016

ASCII art diagrams in Emacs org-mode original ↗

15 Jun 2016

2015

Rare letter combinations and key chords original ↗

1 Feb 2015

Managing Emacs windows original ↗

26 Jan 2015

2014

Emacs resources original ↗

26 Nov 2014

2013

Interview with Sacha Chua original ↗

19 Mar 2013