Incoming links: Ubuntu 23.04
Cross files references to IDs: yes. But no check by default for duplicates when doing automatic ID from title. Just automatically disambiguates with
-1, -2 suffixes, and links take the last one available.Source page splitting: splits at h2 by default. If configurable, likely always af fixed level?
Has some nice image generation from inline code from standard R plotting functions.
Hello world documented at: bookdown.org/yihui/bookdown/get-started.html
Hello world on Ubuntu 23.04 after installing R:The build CLI comes from: stackoverflow.com/questions/50888871/how-to-use-rscript-command-line-tool-to-build-a-book-in-bookdown
sudo R -e 'install.packages("bookdown")'
git clone https://github.com/rstudio/bookdown-demo
cd bookdown-demo
Rscript -e 'bookdown::render_book("index.Rmd")'
xdg-open _book/index.htmlThe installatoin
Rscript -e 'bookdown::render_book("index.Rmd")' takes several minutes, it compiles a bunch of stuff from source apparently. but it did work.Quick overview at stackoverflow.com/questions/1780599/what-is-the-meaning-of-posix/31865755#31865755
Exmples under c/posix:
- c/posix/signal_return.c: stackoverflow.com/questions/37063212/where-does-signal-handler-return-back-to
- c/posix/inet/pton.c:
inet_ptondemo. Adapted fromman inet_ptonon Ubuntu 23.04. Usage:Output:./pton.out 192.187.1.42So we see that the strings was converted to an integer, e.g.:0xc0bb012aSee also: stackoverflow.com/questions/1680622/ip-address-to-integer-c/76520978#76520978- 0xc0 = 192
- 0xbb = 187
- 0x01 = 1
- 0x2a = 42
- c/posix/inet/ntop.c:
inet_ntopdemo. Adapted fromman inet_ptonon Ubuntu 23.04. Usage:Output:./ntop.out 0x01021AA0./ntop.out 0x01021AA0
A compiled executable under
/usr/bin/csvtool, has an Ubuntu 23.04 package: manpages.ubuntu.com/manpages/lunar/en/man1/csvtool.1.htmlThere seems to be no sane filtering mechanism however: stackoverflow.com/questions/46540752/using-csvtool-call-to-filter-csv-in-bash
Build failed with
undefined reference to pcre_config on Ubuntu 23.04: github.com/DavyLandman/csvtools/issues/18Unfortunately it is lacking some basic options, like optional header + selecting column by index on
csvgrep (though csvcut has it). The project seems kind of dead.Also unclear if it allows to filter + print only selected columns.
So dominant that it is usualy called just "zip".
This seems like a decent option, although it has bugs coming in and out all the time! Also it is quite hard to learn to use.
To get started:
- import a clip
- drag it onto the track area
Shortucts:
- Shift + R: cut tracks at current point. You can then select fragments to move around or delete.
- Shift mouse click drag: select multiple clips: video.stackexchange.com/questions/21598/select-range-of-clips-in-kdenlive
To set the video length, search for "set outpoint" on "monitor".
Add subtitles:then drag on top of the video track. To add only to part of the video, cut it up first.
- Effects
- Dynamic text
Preview has no sound on Ubuntu 20.10. Fixed as of Ubuntu 22.04.
Sound worked on Ubuntu 21.04 though, but it then soon crashed with:
= = SET EFFECT PARAM: "rect" = 0=1188 0 732 242
MUTEX LOCK!!!!!!!!!!!! slotactivateeffect: 1
// // // RESULTING REQUIRED SCENE: 1
Object 0x557293592da0 destroyed while one of its QML signal handlers is in progress.
Most likely the object was deleted synchronously (use QObject::deleteLater() instead), or the application is running a nested event loop.
This behavior is NOT supported!
qrc:/qml/EffectToolBar.qml:80: function() { [native code] }
KilledOn Ubuntu 22.04 haven't crashed yet.
Let's try it on SQLite 3.40.1, Ubuntu 23.04. Data setup:
sqlite3 tmp.sqlite 'create table t(x integer, y integer)'
sqlite3 tmp.sqlite <<EOF
insert into t values
(0, 0),
(1, 1),
(2, 2),
(3, 3),
(4, 4),
(5, 5),
(6, 6),
(7, 7),
(8, 8),
(9, 9),
(10, 10),
(11, 11),
(12, 12),
(13, 13),
(14, 14),
(15, 15),
(16, 16),
(17, 17),
(18, 18),
(19, 19),
(2, 18)
EOF
sqlite3 tmp.sqlite 'create index txy on t(x, y)'For a bin size of 5 ignoring empty ranges we can:which produces the desired:
sqlite3 tmp.sqlite <<EOF
select
floor(x/5)*5 as x,
floor(y/5)*5 as y,
count(*) as cnt
from t
group by 1, 2
order by 1, 2
EOF0|0|5
0|15|1
5|5|5
10|10|5
15|15|5And to consider empty ranges we can use SQL which outputs the desired:
genenerate_series + as per stackoverflow.com/questions/72367652/populating-empty-bins-in-a-histogram-generated-using-sql:sqlite3 tmp.sqlite <<EOF
select x, y, sum(cnt) from (
select
floor(x/5)*5 as x,
floor(y/5)*5 as y,
count(*) as cnt
from t
group by 1, 2
union
select *, 0 as cnt from generate_series(0, 15, 5) inner join (select * from generate_series(0, 15, 5))
)
group by x, y
EOF0|0|5
0|5|0
0|10|0
0|15|1
5|0|0
5|5|5
5|10|0
5|15|0
10|0|0
10|5|0
10|10|5
10|15|0
15|0|0
15|5|0
15|10|0
15|15|5OK, there's a billion questions:
- SQL Server
- stackoverflow.com/questions/485409/generating-a-histogram-from-column-values-in-a-database OP did not know the difference between count and histogram :-) But it's the number one Google result.
- stackoverflow.com/questions/19103991/create-range-bins-from-sql-server-table-for-histograms has a minor extra group by twist, but otherwise fine
- stackoverflow.com/questions/16268441/generate-histogram-in-sql-server
- SQLite
- stackoverflow.com/questions/67514208/how-to-optimise-creating-histogram-bins-in-sqlite perf only, benchmarking would be needed. SQLite.
- stackoverflow.com/questions/32155449/create-a-histogram-with-a-dynamic-number-of-partitions-in-sqlite variable bin size, same number of entries per bin
- stackoverflow.com/questions/60348109/histogram-for-time-periods-using-sqlite-regular-buckets-1h-wide time
- MySQL: stackoverflow.com/questions/1764881/getting-data-for-histogram-plot MySQL appears to extend
ROUNDto also round by integers:ROUND(numeric_value, -2), but this is not widely portable which is a shame - stackoverflow.com/questions/72367652/populating-empty-bins-in-a-histogram-generated-using-sql specifically asks about empty bins, which is amazing. Amazon Redshift dialect unfortunately, but answer provided works widely, and Redshift was forked from PostgreSQL, so there's hope. Those newb open source server focused projects that don't use AGPL!
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:which produces the desired:
sqlite3 tmp.sqlite <<EOF
select floor(x/5)*5 as x,
count(*) as cnt
from t
group by 1
order by 1
EOF0|4
5|5
15|1And to consider empty ranges we can use SQL which outputs the desired:
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
EOF0|4
5|5
10|0
15|1Basic example tested on SQLite 3.40.1, Ubuntu 23.04:output:
sqlite3 :memory: 'select 1 union select 2'1
2Two columns two rows:output:
sqlite3 :memory: <<EOF
select * from (values (1, 2), (2, 3))
union
select * from (values (2, 3), (3, 4))
EOF1|2
2|3
3|4Note how duplicates are removed, to keep them we output:
UNION ALL instead:sqlite3 :memory: <<EOF
select * from (values (1, 2), (2, 3))
union all
select * from (values (2, 3), (3, 4))
EOF1|2
2|3
2|3
3|4