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Re: a prime use of regex

Jeremy Falcon14-Jul-23 3:47

Jeremy Falcon

14-Jul-23 3:47

GuyThiebaut wrote:
The interesting part I have found so far is that different text search engines(i.e. 'find' applications) process end of line characters differently, so using the right tool makes a difference too - AgentRansack is not great with end-of-line characters in regular expressions but VS Code seems to work with \r and \n.

Yeah, if I had one gripe about regex it would be that. If it's PCRE compatible regex you're learning though, that'll make it easy enough to adapt to the minor differences in implementation. Just know, if you're using tools like grep or sed in Linux, you'll need to enable extended regex to get something that's more close to PCRE.

Jeremy Falcon

Re: a prime use of regex

PIEBALDconsult3-Jul-23 7:06

PIEBALDconsult

3-Jul-23 7:06

Not clicking that.

I don't see why there would be a video about it rather than an article.

Re: a prime use of regex

Jeremy Falcon3-Jul-23 7:20

Jeremy Falcon

3-Jul-23 7:20

It's a video explaining an article. We just went meta up in here. Laugh | :laugh:

Jeremy Falcon

Re: a prime use of regex

PIEBALDconsult3-Jul-23 7:21

PIEBALDconsult

3-Jul-23 7:21

I'd prefer to read the article.

Re: a prime use of regex

Jeremy Falcon3-Jul-23 7:23

Jeremy Falcon

3-Jul-23 7:23

Voila: A regular expression to check for prime numbers

Jeremy Falcon

Re: a prime use of regex

PIEBALDconsult3-Jul-23 7:26

PIEBALDconsult

3-Jul-23 7:26

Merci

Re: a prime use of regex

RedDk3-Jul-23 7:59

RedDk

3-Jul-23 7:59

Re: a prime use of regex

Slacker0073-Jul-23 10:24

Slacker007

3-Jul-23 10:24

PIEBALDconsult wrote:
Not clicking that.

This is the second time that I know of, where you make a big stink about YouTube links. THEY ARE LEGIT LINKS.

Many biological humans on the planet Earth, use YouTube to learn stuff. Learning stuff on YouTube is cool and awesome and gives you warm fuzzy feelings.

Re: a prime use of regex

Jeremy Falcon3-Jul-23 12:41

Jeremy Falcon

3-Jul-23 12:41

Slacker007 wrote:
THEY ARE LEGIT LINKS.

You never know... could be surfing the web from a text-based terminal browser. Because that's what elite hackers do yo.

For real though, peeps have different learning styles. We should just be happy peeps are learning - regardless of how they do it.

Jeremy Falcon

Re: a prime use of regex

BernardIE53173-Jul-23 11:43

BernardIE5317

3-Jul-23 11:43

are you opposed to viewing YouTube ? if so i do not understand why as it is amazing the ease to which it is possible to learn of many new fascinating subjects and then to learn and study to some mastery . only yesterday i learned of the "HyperLogLog, an algorithm that leverages random chance to count the number of distinct items are in a dataset" also some time ago from a superb series i finally learned what tensors are and of course posted topic . many such superb Thumbs Up | :thumbsup:

series are available . -Best

Re: a prime use of regex

Mircea Neacsu3-Jul-23 16:28

Mircea Neacsu

3-Jul-23 16:28

I don't know why PIEBALD doesn't want to learn from YouTube but I can tell you my reason: because I'm slow. I like to learn in my own pace turning pages one by one, and sometimes going back on a topic and reading it again. This doesn't happen when a guy fast-talks at me. Just give me an old fashioned text and let me dig through it in my own turtle-like speed.

Mircea

Re: a prime use of regex

BernardIE53173-Jul-23 16:54

BernardIE5317

3-Jul-23 16:54

three cheers hip ! hip ! hooray ! on my personal blog i have an article espousing precisely that . also a YouTube video of the text which no-one has viewed . - Best

Re: a prime use of regex

jschell5-Jul-23 6:06

jschell

5-Jul-23 6:06

PIEBALDconsult wrote:
I don't see why there would be a video about it rather than an article.

Myself I prefer reading. But I am a fast reader.

But videos seem the rage. A while ago I attempted to start learning javascript via a video course. Obviously for beginners. He spent about 15 minutes explaining what a variable was. So useless for me.

Re: a prime use of regex

GKP19923-Jul-23 18:12

GKP1992

3-Jul-23 18:12

Sounds like magic, I am wondering how big a number can be tested with the regex hmmm....

Re: a prime use of regex

Daniel Pfeffer4-Jul-23 9:04

Daniel Pfeffer

4-Jul-23 9:04

That, I assume, depends on the limitations of the parser. If the parser is written in C or C++, and they use size_t for counting, that could allow finding all primes until at least 65,535² = 4294836225.

This algorithm is extremely inefficient - O(n²) for each 'n', or O(n³) for all primes less than n. You will run out of time well before you run out of primes.

Freedom is the freedom to say that two plus two make four. If that is granted, all else follows.
-- 6079 Smith W.

Re: a prime use of regex

jschell5-Jul-23 6:14

jschell

5-Jul-23 6:14

Daniel Pfeffer wrote:
You will run out of time well before you run out of primes.

Yep.

But for example.

Largest known prime number - Wikipedia[^]

Re: a prime use of regex

Daniel Pfeffer5-Jul-23 6:29

Daniel Pfeffer

5-Jul-23 6:29

Yes, but Mersenne primes have special formats (in base 2). It's not as if we know all the primes up to 2^82,589,933 - 1.

Freedom is the freedom to say that two plus two make four. If that is granted, all else follows.
-- 6079 Smith W.

CCC 03-07-2023

pkfox2-Jul-23 21:33

pkfox

2-Jul-23 21:33

Unconvinced early growth back markers (7)

In a closed society where everybody's guilty, the only crime is getting caught. In a world of thieves, the only final sin is stupidity. - Hunter S Thompson - RIP

Re: CCC 03-07-2023

OriginalGriff2-Jul-23 22:00

OriginalGriff

2-Jul-23 22:00

Nice!

Ah, sod it - I'll bite...

Unconvinced

early growth   bud
back           DUB
markers           IOUS

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Re: CCC 03-07-2023 - winner !

pkfox2-Jul-23 22:03

pkfox

2-Jul-23 22:03

Nice and easy for Monday

In a closed society where everybody's guilty, the only crime is getting caught. In a world of thieves, the only final sin is stupidity. - Hunter S Thompson - RIP

worldle 527 2/6

jmaida2-Jul-23 15:33

jmaida

2-Jul-23 15:33