gvgai Updated +Created
www.gvgai.net (dead as of 2023)
The project kind of died circa 2020 it seems, a shame. Likely they funding ran out. The domain is dead as of 2023, last archive from 2022: web.archive.org/web/20220331022932/http://gvgai.net/. Marks as funded by DeepMind. Researchers really should use university/GitHub domain names!
Similar goals to Ciro's 2D reinforcement learning games, but they were focusing mostly on discrete games.
They have some source at: github.com/GAIGResearch/GVGAI TODO review
SQL contiguous ranges Updated +Created
stackoverflow.com/questions/17046204/how-to-find-the-boundaries-of-groups-of-contiguous-sequential-numbers/17046749#17046749 just works, even in SQLite which supports all quoting types known to man including [] for compatibility with insane RDBMSs!
Here's a slightly saner version:
rm -f tmp.sqlite
sqlite3 tmp.sqlite "create table mytable (id integer primary key autoincrement, number integer, status integer)"
sqlite3 tmp.sqlite <<EOF
insert into mytable(number, status) values
  (100,0),
  (101,0),
  (102,0),
  (103,0),
  (104,1),
  (105,1),
  (106,0),
  (107,0),
  (1014,0),
  (1015,0),
  (1016,1),
  (1017,0)
EOF
sqlite3 tmp.sqlite <<EOF
SELECT
  MIN(id) AS "id",
  MIN(number) AS "from",
  MAX(number) AS "to"
FROM (
  SELECT ROW_NUMBER() OVER (ORDER BY number) - number AS grp, id, number
  FROM mytable
  WHERE status = 0
)
GROUP BY grp
ORDER BY MIN(number)
EOF
output:
1|100|103
7|106|107
9|1014|1015
12|1017|1017
To get only groups of length greater than 1:
sqlite3 tmp.sqlite <<EOF
SELECT "id", "from", "to", "to" - "from" + 1 as "len" FROM (
  SELECT
    MIN("id") AS "id",
    MIN(number) AS "from",
    MAX(number) AS "to"
  FROM (
    SELECT ROW_NUMBER() OVER (ORDER BY "number") - "number" AS "grp", "id", "number"
    FROM "mytable"
    WHERE "status" = 0
  )
  GROUP BY "grp"
  ORDER BY MIN("number")
) WHERE "len" > 1
EOF
Output:
1|100|103|4
7|106|107|2
9|1014|1015|2
The Simpsons Updated +Created
Video 1.
The Fall of The Simpsons: How it Happened by Super Eyepatch Wolf (2017)
Source. This interesting video essay makes the main point that the Simpsons used to be good because they mocked mainstream. But then they became mainstream, which basically defeated their purpose. Think different from Apple comes to mind.
Hacker News Updated +Created
The most popular programming news sharing forum of the 2010's by far. If your content gets shared there, and it stays on top for a day, the traffic peak will be incredible. Reddit posts are sure to follow.
Basically a programming-only Reddit-lite.
Ciro Santilli had a few of his content shared there as mentioned at the best articles by Ciro Articles.
SQL histogram Updated +Created
Let's try it on SQLite 3.40.1, Ubuntu 23.04. Data setup:
sqlite3 tmp.sqlite 'create table t(x integer)'
sqlite3 tmp.sqlite <<EOF
insert into t values (
  0,
  2,
  2,
  3,

  5,
  6,
  6,
  8,
  9,

  17,
)
EOF
sqlite3 tmp.sqlite 'create index tx on t(x)'
For a bin size of 5 ignoring empty ranges we can:
sqlite3 tmp.sqlite <<EOF
select floor(x/5)*5 as x,
       count(*) as cnt
from t
group by 1
order by 1
EOF
which produces the desired:
0|4
5|5
15|1
And to consider empty ranges we can use SQL genenerate_series + as per stackoverflow.com/questions/72367652/populating-empty-bins-in-a-histogram-generated-using-sql:
sqlite3 tmp.sqlite <<EOF
select x, sum(cnt) from (
  select floor(x/5)*5 as x,
         count(*) as cnt
    from t
    group by 1
  union
  select *, 0 as cnt from generate_series(0, 15, 5)
)
group by x
EOF
which outputs the desired:
0|4
5|5
10|0
15|1
Ubuntu 21.04 Updated +Created
Distributive property Updated +Created
One of the defining properties of algebraic structure with two operations such as ring and field:
This property shows how the two operations interact.
Four-vector Updated +Created
How to contact Ciro Santilli Updated +Created
Ciro Santilli is very happy to meet people with related interests, he really loves his like-minded online friends. Even if you don't have something a specific goal in mind for the contact, please just say hi.
To contact Ciro publicly about any general subject that is not covered in a more specific GitHub repository, including saying hi or suggestions about his website either:
Publicly viewable contact is preferred if possible to more effectively share Ciro's wisdom with the world.
But if you feel more comfortable with private contact, no problem, either:
For other less good methods that will also work, use direct messages of the following profiles from under Section "Accounts controlled by Ciro Santilli":
If you are a privacy freak or are going to tell Ciro state secrets Ciro has this GNU Privacy Guard public key: pubkey.gpg.
Disqus comments were removed from his website in 2019-05-04, a manual dump is available here, removal rationale at: why Ciro Santilli removed Disqus comments from his website in 2019-05-04.
The Playlist Updated +Created
Great reports to how 2022-Ciro Santilli views how OurBigBook.com could go. Ciro can't help to feel that he is a mixture of both of the vision, tech and people guy. Not as extreme as any of them, but more like a well rounded (and less good individually) version of each. High flying bird vs gophers.
The most important projects Ciro Santilli wants to do Updated +Created
They are sorted in order of "most likely to get done first".
Top one: OurBigBook.com.
Wei Dai Updated +Created
Everipedia Updated +Created
Four-gradient Updated +Created
A 4D gradient with some small special relativity specifics added in (the light of speed and sign change for the time).
Metabolic pathway Updated +Created
Some notable examples:
Skew-symmetric bilinear map Updated +Created
History of the University of Oxford Updated +Created
Video 1.
History of Oxford University by Chris Day (2018)
Source. A large part of the video talks about how the insane system of colleges of the University of Oxford came about organically.
Infinity Updated +Created
Chuck Norris counted to infinity. Twice.
There are a few related concepts that are called infinity in mathematics:

There are unlisted articles, also show them or only show them.