Sal Khan Updated 2025-07-16
Like Jimmy Wales, he used to work in finance and then quit. What is it with those successful e-learning people??
Leeuwenhoek microscope Updated 2025-07-16
Lebesgue integral Updated 2025-07-16
"More complex and general" integral. Matches the Riemann integral for "simple functions", but also works for some "funkier" functions that Riemann does not work for.
Ciro Santilli sometimes wonders how much someone can gain from learning this besides the beauty of mathematics, since we can hand-wave a Lebesgue integral on almost anything that is of practical use. The beauty is good reason enough though.
LaTeX Updated 2025-07-16
But too insane, and did not keep up with internet age, and so Ciro wants to kill it now.
Laplace transform Updated 2025-07-16
Ciro Santilli's hardware Lenovo ThinkPad P14s gen4 amd Updated 2026-01-30
Bought: November 2023 during Black Friday sale for £1,323.00 to be Ciro Santilli's main personal laptop.
Six years after, and we are 2x on every key spec (except processor Hz ;-) at about 1/2 the price and 1/2 the weight (though smaller 14" screen for greater portability), so not bad! Customized to max out each hardware spec:
Specs:
- Processor: AMD Ryzen 7 PRO 7840U Processor (3.30 GHz up to 5.10 GHz)
- Graphic Card: Integrated GraphicsThe Ubuntu 23.10 "About system GUI describes its graphics as: Radeon 780M Graphics × 16, which e.g. www.techpowerup.com/gpu-specs/radeon-780m.c4020 documents as running the RDNA 3 microarchitecture.
- Operating System: No Operating System selected upgrade
- Operating System Language: No Operating System Language selected upgrade
- Microsoft Productivity Software: None
- Memory: 64 GB LPDDR5X-6400MHz (Soldered)selected upgrade. Specs at: www.lenovo.com/gb/en/p/accessories-and-software/memory-and-storage/memory-and-storage-hard-drives/4xb1d04758 quotes "64 Gbps", i.e. 8 GB/s.
dd count=1M if=/dev/zero of=tmpgives only 255 MB/s however. - Solid State Drive: 2 TB SSD M.2 2280 PCIe Gen4 Performance TLC Opalselected upgrade
- Display: 14" WUXGA (1920 x 1200), IPS, Anti-Glare, Touch, 45%NTSC, 300 nits, 60Hz
- Camera: 1080P FHD RGB/IR Hybrid with Microphone
- Color: Thunder Black
- Factory Color Calibration: No Factory Color Calibration
- Wireless: Qualcomm Wi-Fi 6E NFA725A 2x2 AX & Bluetooth® 5.1 or above
- Integrated Mobile Broadband: No Wireless WAN
- Ethernet: Wired Ethernet
- Near Field Communication: No NFC
- Fingerprint Reader: Fingerprint Reader
- Keyboard: Black - English (EU)selected upgrade
- Battery: 4 Cell Li-Polymer 52.5Whselected upgrade
- Power Cord: 65W USB-C Slim 90% PCC 3pin AC Adapter - UKselected upgrade
- Electronic Privacy Filter: No ePrivacy Filter
- Adobe Elements: None
- Adobe Acrobat: None
- Adobe Creative Cloud: None
- Security Software: None
- Cloud Security Software: No Cloud Security Software
- Warranty: 3 Year Courier or Carry-in
Identifiers:
- Ethernet MAC address: fc:5c:ee:24:fb:b4
- Wi-Fi MAC address: 04:7b:cb:cc:1b:10
Upon arrival:
Buy research:
- www.phoronix.com/review/thinkpad-p14s-gen4 says Ubuntu running fine
- Intel vs amd: the Intel ones could come with a discrete rtx A500 GPU. GPU likely makes laptop heavier and less power efficient. And both have basically the same benchmark which is crazy:So the only downside is not being able to run CUDA.
- thought about Yoga or other Ultrabook options, but 2x price at same specs, so nah...
Log:
2024-01-17: firmware update:Actually fixed performance mode: askubuntu.com/questions/604720/setting-to-high-performance/1343879#1343879
Vendor: LENOVO
Version: R2FET36W (1.16 )
Release Date: 10/24/2023 Saint Seiya Updated 2025-07-16
This was THE craze thing in Brazil before Pokemon, it was shown from 1994 to 1997. In particular the collectible action figures! It was possibly more popular in Brazil than e.g. in the US: www.quora.com/Why-was-Saint-Seiya-so-popular-in-Brazil
The thing as quite violent, rated for 14-year olds, but no one gave a fuck, 7 yo Ciro was happily watching it. We protect children too much.
That series also had quite a religious feel to it (as obviously suggested by the series English name itself). It must also have been a great motivator to getting young kids into astronomy!
Ciro's favorite character was definitely Andromeda Shun. He was smart and thoughtful, and had the coolest most complex weapon: his chain whips. He's also a bit effeminate, with his pink clothing and a gentle way. Perhaps that is the reason for adult Ciro's mild fascination with the Andromeda Galaxy.
The English name is horrendous... the Portuguese/French name is so much better: Knights of the Zodiac! Saying this in English just reminded Ciro Santilli of the Zodiac Killer. But nevermind.
Saccharomyces cerevisiae Updated 2025-07-16
Minimization project: en.wikipedia.org/wiki/Saccharomyces_cerevisiae#Synthetic_yeast_genome_project | syntheticyeast.org/
Ruth Lawrence Updated 2025-07-16
en.wikipedia.org/wiki/Ruth_Lawrence
When Lawrence was five, her father gave up his job so that he could educate her at home.
www.dailymail.co.uk/femail/article-3713768/Haunting-lesson-today-s-TV-child-geniuses-Ruth-Lawrence-Britain-s-famous-prodigy-tracked-father-drove-heard-troubling-tale.html
he had tried it once before - with an older daughter, Sarah, one of three children he had by a previous marriage.That experiment ended after he separated from Sarah's increasingly concerned mother, Jutta. He soon found a woman more in tune with his radical ideas in his next spouse, Sylvia Greybourne
Kondo effect Updated 2025-07-16
If you adda bit of impurities to certain materials, at low temperatures of a few Kelvin their resistivity actually starts increasing if you go below a certain critical temperature.
Kondo effect graph for gold with added impurities
. Source. 
Know Your Meme Updated 2025-07-16
KISS principle Updated 2025-07-16
The software engineer phrasing of simplicity is the ultimate sophistication.
Like all other principles, it is not absolute.
But it is something that you should always have on the back of your mind.
You aren't gonna need it is closely related, as generally the extra unnecessary complications are set in place to accommodate useless features that will never be needed.
Kingdom (biology) Updated 2025-07-16
Kinetic theory of gases Updated 2025-07-16
Theory that gases are made up of a bunch of small billiard balls that don't interact with each other.
This theory attempts to deduce/explain properties of matter such as the equation of state in terms of classical mechanics.
Kimchi Updated 2025-07-16
View top posts of previous months or years in Reddit Updated 2025-07-16
No good per-sub way as of 2022:
- www.reddit.com/r/help/comments/27eziq/view_top_posts_of_a_specific_timespan/
- www.reddit.com/r/help/comments/9ebxl3/how_do_i_find_old_posts_on_a_subreddit/
- www.reddit.com/r/help/comments/aywras/how_do_i_search_reddit_for_posts_in_a_specific/
- www.reddit.com/r/modhelp/comments/etsomx/how_to_get_top_posts_of_past_months_of_subreddit/
- www.reddit.com/r/redditdev/comments/kaf1yz/finding_top_post_of_specific_month/
- www.reddit.com/r/changelog/comments/k663qy/introducing_rereddit_go_back_in_time_to_see_top/
- www.reddit.com/r/help/comments/stui9i/is_it_possible_to_look_up_the_top_posts_of_the/
Place and route Updated 2025-07-16
Given a bunch of interlinked standard cell library elements from the logic synthesis step, actually decide where exactly they are going to go on 2D (stacked 2D) integrated circuit surface.
Sample output format of place and route would be GDSII.
pip (package manager) Updated 2025-09-09
How many stupid bugs. How many stupid bugs do we need to face???
- this fucking train-wreck cannot come up with a unified documented way of specifying dependencies:So basically
- stackoverflow.com/questions/14399534/reference-requirements-txt-for-the-install-requires-kwarg-in-setuptools-setup-py
- stackoverflow.com/questions/26900328/install-dependencies-from-setup-py
- stackoverflow.com/questions/30797124/how-to-use-setup-py-to-install-dependencies-only/63743115
- stackoverflow.com/questions/6947988/when-to-use-pip-requirements-file-versus-install-requires-in-setup-py
requirements.txtis thepackage-lock.json. But how to generate it cleanly? You would need to create a virtualenv? pip searchwas disabled in 2020: stackoverflow.com/questions/17373473/how-do-i-search-for-an-available-python-package-using-pip. WTF. If server load is a problem, just create a token system! It is hard to understand how such a popular language can't raise enough money to keep such simple server functionality running.
Keyhole Inc. Updated 2025-07-16
Keep debug notes Updated 2025-07-16
When debugging complex software, make sure to keep notes of every interesting find you make in a note file, as you extract it from the integrated development environment or debugger.
Especially if your memory sucks like Ciro's.
This is incredibly helpful in fully understanding and then solving complex bugs.
There are unlisted articles, also show them or only show them.