Hacker News: mjcohen

New comment by mjcohen in "Verschlimmbesserung: The Word Your Software Updates Need"

mjcohen — Fri, 28 Aug 2026 22:56:04 +0000

The Reason Foundation has a series of Youtube videos about things that were done with good intentions but ended up making things worse.

New comment by mjcohen in "What happens if an entire class of workers loses faith in their careers"

mjcohen — Fri, 07 Aug 2026 19:43:39 +0000

So glad I am retired.

New comment by mjcohen in "Making Referential Stability a Type"

mjcohen — Fri, 31 Jul 2026 22:57:16 +0000

For some reason I read this as

Making Referential Stupidity a Type

New comment by mjcohen in "Show HN: Writemark, a dependency free web component for inline Markdown editing"

mjcohen — Sun, 26 Jul 2026 03:27:13 +0000

For math.stackexchange.com which uses MathJax, I use MacDown, a markdown editor with parallel windows, one showing the MathJax and the other (in real time) the rendered math. I find it essential.

I enter my math directly into the editor without writing anything on paper. Works for me. The ability to copy and paste is invaluable.

New comment by mjcohen in "LuaJIT 3.0 proposed syntax extensions"

mjcohen — Thu, 25 Jun 2026 01:58:03 +0000

The ternary operator is easy to nest if you put each clause on a separate line. Then it looks just like nested if-then-else.

New comment by mjcohen in "Computer use in Gemini 3.5 Flash"

mjcohen — Thu, 25 Jun 2026 00:01:19 +0000

Years ago, I used Acrobat to extract tables from a PDF. Had to do it manually, but it pasted nicely into Excel.

New comment by mjcohen in "The IRS Moved IT and HR Staff to Process Taxes. It's Not Going Well"

mjcohen — Mon, 08 Jun 2026 21:32:21 +0000

As usual, anything Trump and his minions touch turns to garbage.

New comment by mjcohen in "First Commodore PET sold, June 5, 1977"

mjcohen — Sat, 06 Jun 2026 21:32:23 +0000

I believe that I got the first external cassette drive for the PET on the west coast. Only used it a very few times. The big boost was when I got the floppy disk drive. I could do anything!

New comment by mjcohen in "Entanglement Builds Space-Time. Now "Magic" Gives It Gravity"

mjcohen — Fri, 05 Jun 2026 23:02:38 +0000

For a nice introduction to relativity, look at The Einstein Theory of Relativity: A Trip to the Fourth Dimension by Lillian R. Lieber. $15 on Amazon. Written in 1945 and still quite good.

New comment by mjcohen in "The Pack That Killed the Pack Mule"

mjcohen — Fri, 29 May 2026 03:24:24 +0000

I enjoyed this article. I always find it interesting how things came to be and how individual contributions made things happen.

New comment by mjcohen in "Ping-pong robot beats top-level human players"

mjcohen — Thu, 23 Apr 2026 00:55:10 +0000

If you believe them.

New comment by mjcohen in "Ping-pong robot beats top-level human players"

mjcohen — Thu, 23 Apr 2026 00:37:18 +0000

As Victor said, his parents were very upset when they came home and found him in front of a roaring fire, because they did not have a fireplace.

New comment by mjcohen in "Approximating Hyperbolic Tangent"

mjcohen — Thu, 23 Apr 2026 00:31:18 +0000

Looks interesting. Should start with a definition of the Hyperbolic Tangent. It is only about 2/3 of the way that the definition occurs in a discussion of computing exp(x).

New comment by mjcohen in "Make macOS consistently bad (unironically)"

mjcohen — Fri, 27 Mar 2026 22:28:23 +0000

Damn. Never knew that. TIL

New comment by mjcohen in "First Website (1992)"

mjcohen — Thu, 26 Feb 2026 02:12:20 +0000

In the mid 70's, I was a graduate CS student at USC's Information Sciences Institute. I remember my feeling of awe when I used Arpanet (or was it Darpanet) to log into London and do stuff there. Wow!

New comment by mjcohen in "We're no longer attracting top talent: the brain drain killing American science"

mjcohen — Fri, 20 Feb 2026 00:35:45 +0000

Trump is clearly winning his war on America.

New comment by mjcohen in "Faster Than Dijkstra?"

mjcohen — Fri, 13 Feb 2026 23:32:52 +0000

Not if the ratio between the largest and smallest floats is very large (2^(2^n)) where n is the number of bits in the exponent.

New comment by mjcohen in "Using secondary school maths to demystify AI"

mjcohen — Fri, 12 Dec 2025 23:07:02 +0000

Like the old saying:

Military justice is to justice as military music is to music

New comment by mjcohen in "Terence Tao: At the Erdos problem website, AI assistance now becoming routine"

mjcohen — Mon, 24 Nov 2025 01:55:03 +0000

(I saw this on a math department bulletin board about 1960)

A theorem both deep and profound States that every circle is round But in a paper by Erdos Written in Kurdish A counterexample is found

New comment by mjcohen in "Project Euler"

mjcohen — Thu, 13 Nov 2025 02:14:05 +0000

Did you use the regular version or the one with multiple-precision values?