Stacks Project Updated 2025-07-16
- Renders: stacks.math.columbia.edu/. HTML is one tiny section per page, making it unreadable.
- LaTeX source: github.com/stacks/stacks-project
The book is very dry, extremelly boring unfortunately. Definition and theorem only for the most part.
Rich people who create charitable prizes are often crooked Updated 2025-07-16
A friend of mine who's a rich man - he invented some kind of simple digital switch - tells me about these people who contribute money to make prizes or give lectures: "You always look at them carefully to find out what crookery they're trying to absolve their conscience of."
Rickrolling Updated 2025-07-16
Riemann integral Updated 2025-07-16
The easy and less generic integral. The harder one is the Lebesgue integral.
Computer science course of the University of Cambridge Updated 2025-07-16
The courses are highly open, almost everything is given publicly except solutions, many of which are given to teachers only. Well done!
Past exam papers index: www.cl.cam.ac.uk/teaching/exams/pastpapers/
www.cl.cam.ac.uk/teaching/2223/
- www.cl.cam.ac.uk/teaching/2223/part1a.html year 1
- Michaelmas term
- www.cl.cam.ac.uk/teaching/2223/Databases/
- past exams:
- questions: public www.cl.cam.ac.uk/teaching/exams/pastpapers/t-Databases.html
- solutions: paywalled
- slides: public e.g. www.cl.cam.ac.uk/teaching/2223/Databases/djg-materials/databases_2223_1to4-B.pdf
- problem sheets:
- questions: public e.g. www.cl.cam.ac.uk/teaching/2223/Databases/djg-materials/supervision-1.html
- solutions: not available
- past exams:
- www.cl.cam.ac.uk/teaching/2223/Databases/
- Lent term
- Discrete mathematics
- problem sheets:
- question: public e.g. www.cl.cam.ac.uk/teaching/2223/DiscMath/solutions/DiscMaths1_Sols.pdf
- solutions: public e.g. www.cl.cam.ac.uk/teaching/2223/DiscMath/solutions/DiscMaths1_Sols.pdf
- problem sheets:
- ALgorithms 1
- lecture notes: www.cl.cam.ac.uk/teaching/2223/Algorithm1/2022-2023-stajano-algs1-handout.pdf
- problem sheet:
- questions: www.cl.cam.ac.uk/teaching/2223/Algorithm1/2022-2023-stajano-algs1-exercises.pdf
- solutions: not available
- www.cl.cam.ac.uk/teaching/2223/Algorithm1/
- Discrete mathematics
- Michaelmas term
Connect two computers directly without a router with an Ethernet cable Updated 2025-07-16
For IP-level communication, askubuntu.com/questions/22835/how-to-network-two-ubuntu-computers-using-ethernet-without-a-router/116680#116680 just worked between P51 and P14s both on Ubuntu 23.10 connected with a regular Cat 5e cable.
On both machines, first we found the Ethernet cable interface name with the which outputs on the P41s:so the interface was
ip CLI tool:ip a1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: enp1s0f0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
link/ether fc:5c:ee:24:fb:b4 brd ff:ff:ff:ff:ff:ff
3: wlp2s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
link/ether 04:7b:cb:cc:1b:10 brd ff:ff:ff:ff:ff:ff
inet 192.168.1.123/24 brd 192.168.1.255 scope global dynamic noprefixroute wlp2s0
valid_lft 61284sec preferred_lft 61284sec
inet6 fe80::3597:15d8:74ff:e112/64 scope link noprefixroute
valid_lft forever preferred_lft foreverenp1s0f0, because wlp is wireless and lo is localhost.So on the P14s we assign an IP of 10.0.0.10 to the P51:
sudo ip address add 10.0.0.10/24 dev enp1s0f0Then on the P51 analogously, giving IP of 10.0.0.20 to the P14s:
sudo ip address add 10.0.0.20/24 dev enp0s31f6And after that, P14s can:and P51 can:
ping 10.0.0.10ping 10.0.0.20 Sexual innuendo Updated 2025-07-16
ImageMagick HOWTO Updated 2025-07-16
Riesz-Fischer theorem Updated 2025-07-16
A measurable function defined on a closed interval is square integrable (and therefore in ) if and only if Fourier series converges in norm the function:
Ring (mathematics) Updated 2025-07-16
A Ring can be seen as a generalization of a field where:
- multiplication is not necessarily commutative. If this is satisfied, we can call it a commutative ring.
- multiplication may not have inverse elements. If this is satisfied, we can call it a division ring.
The simplest example of a ring which is not a full fledged field and with commutative multiplication are the integers. Notably, no inverses exist except for the identity itself and -1. E.g. the inverse of 2 would be 1/2 which is not in the set. More specifically, the integers are a commutative ring.
The simplest non-commutative, non-division is is the set of all 2x2 matrices of real numbers:Note that is not a ring because you can by addition reach the zero matrix.
- we know that 2x2 matrix multiplication is non-commutative in general
- some 2x2 matrices have a multiplicative inverse, but others don't
RNA-Seq Updated 2025-07-16
Wayland Updated 2025-07-16
They've been trying to get it to work forever, and it's beeen buggy forever:
Became the default on Ubuntu 21.04: www.omgubuntu.co.uk/2021/01/ubuntu-21-04-will-use-wayland-by-default
First block not mined by Satoshi Updated 2025-07-16
Sitare Foundation Updated 2025-07-16
Personal knowledge instance Updated 2025-07-16
Complex coordinate space of dimension 2 Updated 2025-07-16
Robert O'Callahan Updated 2025-07-16
He quit Mozilla in 2016 to try and commercialize an
rr extension called Pernosco.But as of 2022, he advertised himself as part of "Google Research", so maybe that went under, sample source: archive.ph/o9622. TODO when did he start? There's apparently an unrelated homonym: www.linkedin.com/in/rob-ocallahan/
He's apparently very religious, and very New Zelandish, twitter.com/rocallahan auto-describes:Terry A. Davis and D. Richard Hipp come to mind. One is tempted to speculate a correlation even, the proportion amongst systems programmers feels so much higher than in other areas of programming! Maybe it is because you have to be a God to do it in the first place.
Christian. Repatriate Kiwi.
Robert O'Callahan interview by Toby Ho (2022)
Source. Roberto Rossellini Updated 2025-07-16
His films Blaise Pascal (1972) and Cartesius (1974) have the greatest scenery and wardrobe ever. The eerie horror movie soundtrack is also very interesting. Ciro was weirdly reminded of Cosmos: A Personal Voyage (1980).
Roche Biochemical Pathways Updated 2025-07-16
Rolls-Royce Updated 2025-07-16
There are unlisted articles, also show them or only show them.