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/sci/ - Science, Technology, Engineering, and Mathematics

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New Textbook/Book Request Thread deadbabies ## Mod ## 13/08/25(Sun)06:03 No. 15270 ID: f34135 [Reply] Stickied

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First off, hello there, I'm deadbabies, and I will be taking over as /sci/ moderator. Rules will remain the same. Please use the report function if you see posts that violate the rules, but also do not abuse it.

I have officially expanded the scope of /sci/ a bit. You may discuss Science, Technology, Engineering, and Mathematics here now. No science is discriminated against as long as it's of the peer-reviewed variety. If someone wants to discuss Anthropology or Social Science, by all means, let them. If you do not like it, just don't post in the thread.

The IRC channel #/sci/ is now (finally) re-registered and I am running as operator on here. Feel free to stop by and say hi. I do leave my computer idling on IRC, so check back or leave me a message if you have any ideas, suggestions, or just want to tell me off. You can get onto #/sci/ by joining the server irc.7chan.org at port 6667. You can also use SSL at port 6697 but you will have to set your client to accept invalid certificates.

ADDITIONALLY and IMPORTANTLY I have had several requests on IRC regarding the old Ebook FTP that we used to have. Unfortunately, the mod who ran it entered the military and no longer runs or maintains it. I have no plans to make another one, but if one of you guys would like to, by all means advertise here.

That being said, I'm just going to leave this link here:


You may find what you seek here.

I will be unstickying the old ebook/source articles thread. Please post any new ebooks/source articles here, and feel free to post any working links from the old thread there; I will eventually be deleting it.
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Anonymous 22/06/29(Wed)16:52 No. 18285 ID: ed20e1

If you suffer from insomnia, then I can imagine how much it interferes with your life. I had insomnia for a long time, but I eventually solved this problem with cbd gummies. In general, you can choose any form of cbd, this online store https://www.cornbreadhemp.com/products/full-spectrum-cbd-gummies has a fairly large selection of cbd supplements, but cbd gummies are my favorite because they are delicious.

RMS "Approves" GRSecurity GPL violation, says "may" be Anonymous 23/09/06(Wed)13:15 No. 18687 ID: 5947a7 [Reply]

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>From: Richard Stallman
>Sent: Tuesday, September 5, 2023 at 08:59:56 PM EDT
>Subject: Re: Could you please sue GRSecurity.
>[[[ To any NSA and FBI agents reading my email: please consider ]]]
>[[[ whether defending the US Constitution against all enemies, ]]]
>[[[ foreign or domestic, requires you to follow Snowden's example. ]]]
> > RMS: please. You sued Cisco.
> > Yet this is allowed? (they violate the copyright on your GCC, in addition to the Linux Kernel)
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Anonymous 23/09/06(Wed)13:47 No. 18688 ID: 5947a7

And, Yes I am a lawyer.
Yes GRSecurity is contravening the "u can't put any additional restrictions not mentioned in the text of this license" clause of the GPL; vs both the Linux Kernel and the GCC "plugins" they distribute subject to their(GRSecurity's) "no redistribution" clause (which has been effective: the source has not leaked: GRSecurity has made it's patches to the linux kernel and GCC proprietary)

The GCC "plugins" are non-separable derivative works, just as their linux-kernel patches are non-separable derivative works. They only work regarding the parent work.

Don't believe me: read the real player case then. Go on. Read it. If you even make some 3rd party program that messes with the look of the other program you can be violating the copyright on the other program. Go read the case. There are others but when I tell you people you just say "DURR WHY NOT JUST DISTRIBUTe A DiFF and GeT aRoUnD the GpL thaT wAy"

Why won't RMS sue? Because he has women lawyers surrounding him who don't want to do shit. That's actually their job: to dissuade RMS etc from taking any Copyright action and upsetting the "GPL-as-effectivly-BSD-Licensed" status-quoe that emerged.

The only courageous one was Bruce Perens who fought abit of the good fight.
Note: ANY of these federal copyright lawsuits would cost probably half-a-million or more for the Copyright owner to prosecute.
RMS's foundation doesn't want to do it.
GPL rots in it's grave.

Anonymous 23/09/22(Fri)16:27 No. 18690 ID: be6f8f

I have no idea about the details, but I do know one thing: the GPL is cancer that needs to go away. If companies are starting to test the waters then let them. If the FSF doesn't want to pursue legal action then let them. Hopefully people will stop taking the GPL seriously. I'll dance on its conceptual grave the day that happens.

And yeah, obviously the FSF has nothing to do with the Linux Foundation.

GnuPG DOWNLOADS.zip 230 MB Encryption Tool Anonymous 23/06/18(Sun)08:17 No. 18676 ID: ae463f [Reply]

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GnuPG DOWNLOADS.zip 230 MB Encryption Tool

Contains these 4 videos on how to use the GnuPG - Cleopatra encryption tool to encrypt files.

How To Use GPG To Encrypt And Decrypt Messages.mp4
How To Use PGP Encryption - gpg4win Kleopatra Tutorial.mp4
Using GPG (GnuPG) To Encrypt and Decrypt A File.mp4
How to use GPG to encrypt and decrypt messages - Kleopatra Tutorial Encrypting and Decrypting Files.mp4


Old Technology Thread Anonymous 21/02/10(Wed)07:42 No. 17263 ID: 2c3397 [Reply]

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ITT Post/discuss old technology.

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Anonymous 23/05/16(Tue)10:37 No. 18511 ID: 88736e

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Tanks need a turret.

Anonymous 23/07/23(Sun)02:48 No. 18682 ID: e00e46

This was my whole child hood right there

Anonymous 23/07/31(Mon)17:36 No. 18684 ID: 64afbd

File 169081778082.jpg - (95.90KB , 1600x1200 , demo.jpg )


Prime test Anonymous 22/02/17(Thu)19:25 No. 18131 ID: f85074 [Reply]

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Today one of my recurring dream characters named Jennifer Zemblini gave me a prime number test that correctly validated the first few hundred prime numbers in under 3 seconds using C# code I wrote to validate her primality test!

I wanted to share the primality test with you all now.

It uses only simple division, addition and subtraction. And three variables called n, A and B.

n is defined as the number being tested for primeness. A0 is n-2 and B0 is 2.

Then apply this procedure: Divide A by B, if it is not a clean division, meaning there is a remainder, add one to B and subtract one from A, and repeat this step until B approaches one-half of n.

If A can never divide evenly into B then n is prime.

For example with n=9, which is not prime: A = 9-2. B =2. 7/2 is not even. 6/3 does evenly divide with result 2. And 3 is a factor of 9 also.

But for a prime like 13: 11/2... 10/3... 9/4... 8/5... 7/6... None of these divide cleanly with no remainder, therefore 13 is prime.
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Anonymous 22/02/21(Mon)05:33 No. 18143 ID: bf7eac

>quotient is still zero when dividend = n, thus n % m == (n + m * k) % m for any integer k.
This is an error. I meant to say that the remainder is still zero.

Anonymous 22/06/19(Sun)13:11 No. 18281 ID: e5a2d8

I want to clarify that you don't need to sweap across the entire half of the number. If there are no such A and B before B is greater than sqrt(n). There won't be any at all.
And what you did is just a fancy way to do Euclid primality test by checking the first sqrt(n) numbers if any divide n. Since you are checking if B divides A which is none but n-B
Since for all B, B divides itself
So B divides the sum of n-B and B = n
So you're back with the normal primality test, maybe even worse cause you are wasting time computing n-B.
Your Jennifer is retarded.

Anonymous 23/07/26(Wed)00:04 No. 18683 ID: cbe355

Your primality test is 100% right and there is no exception to it. The only problem is that it's not only inefficient (it has an asymptotic complexity of O(n)) but it is basically testing the divisibility of n by any number in the range (2,n/2).

Anonymous 23/07/19(Wed)01:17 No. 18678 ID: 6915e2 [Reply]

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Why do people use math symbols when they are teaching new concepts? The symbols should only be used for when you are actually doing work but when you are explaining something you should just explain it and then show the symbols.
It took me like 30 minutes to figure out what it meant for a k-tuple to be admissible because all the explanations I could find online used the symbols and terms to explain it without actually doing any explanation.

Anonymous 23/07/19(Wed)01:19 No. 18679 ID: 6915e2

It turns out it's actually an extremely simple concept but it took me 30 minutes because the internet is so bad at explaining things. I think that most of these people don't even know what it means themselves so they don't know how to explain it right.

Anonymous 23/07/19(Wed)01:20 No. 18680 ID: 6915e2

I'm just saying people should improve the way they teach stuff because it would lead to more progress that's all. I'm not complaining.

Anonymous 23/07/20(Thu)08:22 No. 18681 ID: 19b952

Because natural language is ambiguous. Formal language was invented to be able to convey meaning unequivocally. That it also makes the meaning more difficult to extract is an unfortunate but acceptable side-effect.

That said, I've seen mathematical notation used very poorly. The worst example I can think of is the Ethereum yellow paper, in the specification of the EVM. The state variables and their modification functions are expressed using single-character symbols, which forces the reader to keep track of the meaning of some 40-something symbols, IIRC.

bank account getting drained from hackers Anonymous 17/07/17(Mon)01:09 No. 16526 ID: 030037 [Reply]

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Theoretically, how fucked up would I be if someone used a keylogger on my machine for a few month and leaked my bank account details (online password, PIN, security questions etc) on the Darkweb?

Not worried at all but I just wonder how good these computer hackers are at clearing accounts. Aren't there limits depending on the level of your account? They definitely can get around I.P alerts when accounts are accessed in different countries.

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Anonymous 17/11/06(Mon)19:26 No. 16575 ID: 7b1c18

Hackers prefer to target businesses for large transactions, because they know few people have $100,000 lying around, while a huge number of businesses have access to that much credit.

Anonymous 18/04/15(Sun)20:14 No. 16647 ID: a66c44

There is this new satoshi dice address for BTC.
Address is bc1quykuahxrjx6d3h6ga4rkyg0hl5e59tcthqyhw6.

I found this while scanning pastebin

Here are the instructions on how to verify the provably fair roll.

Anonymous 23/06/22(Thu)14:04 No. 18677 ID: 88736e

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Let me ponder your enquiry

start learning about computers Bigattao 16/03/10(Thu)06:19 No. 16297 ID: 00af9a [Reply]

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Hi sci,
I'm a noob about computers and going to do college of Computer Engineering. I don't know even how to start learning. Can somebody give a tip?

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Anonymous 23/02/10(Fri)12:38 No. 18483 ID: c9d146

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Modern vehicles have a lot of chips these days...

Anonymous 23/05/24(Wed)11:44 No. 18514 ID: 88736e

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Taiwan and South Korean are the manufacturer of the most advanced microchips

Anonymous 22/07/21(Thu)13:44 No. 18308 ID: 9ce3c9 [Reply]

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Science is evil...

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Anonymous 23/02/18(Sat)03:59 No. 18495 ID: c9d146

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V/STOL is sexy

Anonymous 23/05/19(Fri)11:55 No. 18512 ID: 88736e

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This is the way

Anonymous 23/05/25(Thu)11:43 No. 18515 ID: 88736e

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Sunny Day

Request: Post HD images of technology Anonymous 17/10/08(Sun)00:10 No. 16561 ID: 864454 [Reply]

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Hey guys, I recently started a computer science class in college and my networking teacher who is the head of the IT department wants us to impress him with the best personalization of our desktops.

> inb4 impress him with your computer programming skills as opposed to flashy images

No anons, No. The motto that he always repeats is that it's important to be "all rounded". He's seen lots of autist computer geeks who are geniuses at what they do but are pretty much mediocre/shit at nearly everything else in their life (social skills, organisation of themselves, writing CV's).

I would like to show off images that highlight an interest in tech along with high quality photography; so if I may ask you kindly to post your favorite images

> I would to the other chan but those fags banned me since June of this year and my shitty ISP hasn't renewed my "dynamic" I.P. address for 4 months.

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Anonymous 17/12/01(Fri)08:53 No. 16591 ID: 86f262

personalization of the desktop doesn't sound like a assignment....

if you want to make it personal, you need to take the picture yourself. There is nothing special about a good quality pic from the web.

For offtopic, i second this guy -> >>16570
Offcourse i would choose the ugly powermachine instead of nice looking computer that barely even computes.

Anonymous 22/12/26(Mon)03:26 No. 18423 ID: c9d146

Ask for some photos from James Webb

Anonymous 23/05/24(Wed)11:42 No. 18513 ID: 88736e

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Absolute Zero

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