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

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need calculations without sci notation _kp_ 14/05/30(Fri)22:51 No. 15694 ID: 105678 [Reply]

File 14014830663.jpg - (100.20KB , 238x579 , rs.jpg )

Hello Gents & Ladies,

I need to calculate x=2^n
where n goes from 0 to 319 in interval of 1.

I tried MATLAB etc but they all start converting the result to exponential form whereas I need the result to be accurate upto unit position.

Can any wise person suggest a way/software to calculate this ( and preferably do it for all values of n so that I don't have to manually calculate for each) ?

Your time & thoughts are much appreciated.

24 posts and 4 images omitted. Click Reply to view.
Anonymous 15/02/09(Mon)20:07 No. 16051 ID: 58e797

You do know using arbitrarily large numbers is pointless, all you're doing is obscuring any point you're trying to make behind incomprehensibly vague values even the most autistic of us would struggle with. Why not chuck in a googolplex or two while you're at it.

Here's a nice article that should help you understand why using real-world values is more useful when trying to make a point:

Anonymous 15/02/09(Mon)20:36 No. 16052 ID: e3615c

>You do know using arbitrarily large numbers is pointless
The pointlessness is a property of the operation you'll apply to the value, not of the value itself. For example, 1.067993e+96 and 2^319 are not interchangeable if you're going to use them in cryptographic operations.
In particular, OP originally stated,
>I need the result to be accurate upto unit position

>all you're doing is obscuring any point you're trying to make behind incomprehensibly vague values even the most autistic of us would struggle with.
The numbers are so large because someone settled with a 1e-13% error in a 96-digit value. The error is an 81-digit value.

Anonymous 15/03/31(Tue)05:52 No. 16080 ID: da1583

was going to reply to the content of the message but the picture was too distracting, sry

Anonymous 15/01/17(Sat)18:16 No. 16028 ID: 36bbdb [Reply]

File 142151497518.jpg - (44.80KB , 600x600 , LOOMINATI.jpg )

Kay guys. Not sure if I should post this here or in Tech Support but I need some basic tech assistance, nothing is borked. I bought a Windows phone and I'm disgusted with its obsession on finding my location and harvesting my data, often without my permission. When I tell apps and programs they can't use GPS to stalk me or gather my data, they refuse to work--even though the functions they perform are not reliant on positioning.

What can I use to keep the phone from being a little Big Brother all the time? I'm not worried about the gubbermint, they are welcome to my porn and terrifying Internet history. I just hate being advertised to and watched by corporations everywhere I go. Are there any add-ons I can use to make the phone more secure/more resilient to casual data trawling?

I'll take this to tech-help if I have to, but I wanted to ask you chaps first. Thanks in advance.

Anonymous 15/01/17(Sat)18:17 No. 16029 ID: ab9f96

I have a windows phone and it rarely does this. Mostly because I don't have any apps.

solution? Use phone for text/calls only and turn off data. gj

A nice initiative Anonymous 15/01/09(Fri)20:44 No. 16024 ID: c7d0c5 [Reply]

File 142083267722.jpg - (8.75KB , 100x100 , 7moon.jpg )

It's nice that this emerging site tries to introduce progressively the mathematics and the science at the people.
we hope that they follow other chapters, as they promise on their home page.

how to make airplane Anonymous 15/01/04(Sun)17:37 No. 16019 ID: 61d208 [Reply]

File 142038945866.jpg - (548.56KB , 1280x720 , F24F35.jpg )


Cryptoforums.net Technology Forum Cryptoforums.net Technology Forum 14/05/13(Tue)10:25 No. 15656 ID: 288b60 [Reply]

File 139996955137.png - (8.43KB , 82x77 , CF-logo.png )

Hello chans of the internet. We at https://cryptoforums.net have created a MyBB forum dedicated to the discussion of things like Bitcoin, Privacy, Security, Cryptography, GNU/Linux, Philosophy, Politics, Freedom, Cryptocurrency, Hacking and many other general subjects. We are currently in our early stages and we want to invite more members. If you like any of those subjects you should come check us out! We also respect anyone's opinion even if negative so give us all your positive/negative support/criticism!

7 posts omitted. Click Reply to view.
Anonymous 14/08/11(Mon)18:38 No. 15815 ID: d9f5aa

the joke's getting old, shillfag.

OP your forum would be a lot more appealing if it didn't require an email.
trashmail makes it easy but waiting for the email to arrive is a fucking dealbraker.
I'd probably rather enter a fucking google recaptcha and have my everchanging dynamic IP logged by some useless waste-of-money agency than wait for a shitty activation mail (and possibly still get logged if my ISP or trashmail provider is sharing data as much as google does).

Anonymous 14/08/11(Mon)18:39 No. 15816 ID: d9f5aa

>>15662, not 199869 obv.

Registration requires captcha, but none displayed for me Anonymous 15/01/02(Fri)05:55 No. 16015 ID: 226b1d

I've tried to register on cryptoforums three times tonight, using Opera, FireFox, and IE. In all three browsers, I agree to the terms, populate the fields, and submit the form, to be greeted with:

Please correct the following errors before continuing:
•The image verification code that you entered was incorrect. Please enter the code exactly how it appears in the image.

There is no captcha image to enter. There's a question to answer, which I answered correctly each time.

Is the new user registration broken, or am I the only one having this issue?

Also, your Contact Us mailto link is broken. It contains no email address. Ergo, I could find no way to reach a site administrator, hence the post here.


Anonymous 13/07/18(Thu)15:31 No. 15206 ID: 9083c1 [Reply]

File 137415428455.jpg - (94.22KB , 640x569 , turkey_roast.jpg )

I might sound like an idiot for asking this, but can somebody explain the science behind the following:

When you're grilling two steaks over a flame, it takes the same amount of time, whether it's just one or two steaks.

When you're roasting two turkeys inside an oven, it usually takes 1.5 to 1.8 times longer than when there's just one turkey inside.

Why doesn't it take the same amount of time as it does when grilling two steaks over a flame?

Why am I an idiot for not understanding this?

2 posts omitted. Click Reply to view.
CandleJack 13/07/23(Tue)22:45 No. 15220 ID: 2f260d


Ovens are not perfectly efficient. With the one turkey, say 50% of the energy goes toward heating it, while the remainder heats the air or escapes outside. With two turkeys, 75% of the heat goes to them, while the rest heats the air (which there is less of because the oven is more full) or escapes.

Have you heard how a full refrigerator is more efficient than an empty one? That's because it takes more energy to heat or cool air (and maintain it) than it does to heat or cool an object. It's just like that, but in reverse. Because there is less air in the oven, it doesn't waste energy heating that air; the conserved energy goes into heating the other turkey.

Anonymous 13/07/24(Wed)01:59 No. 15221 ID: 9083c1

Now I get it, thanks a lot!

Anonymous 14/12/30(Tue)20:13 No. 16012 ID: a607c9


Thats incorrect. It is a common misunderstanding that air needs more energy to cool down in a fridge than solid or liquid mass(like bottles full of water) does.
While it is true that a full fridge uses less energy than a empty one, that is only the case if you leave the solid mass inside. Air has a thermal capacity of roughly 1 J/gK (Joule per gram and Kelvin ). The thermal capacity of Water is very roughly 4 times higher. This means you would need 4 times the energy to cool down (or heat up) 1 kg of Water than 1 kg of air. A fridge is typically less than 200 liters big inside, which is 0,25 Kg of air. If you put something in your fridge which is at least 0,065 kg (or 65 g) heavy and mostly made of water, it will take more energy to cool down than if all the air inside the fridge would have changed.

So why is it still more efficient to have a full fridge than an empty one?
When you open the fridge there is normally no liquid or solid mass leaking. However the cold air is escaping even if you don't want cold air in your kitchen. Thus the air loss is energy loss. If you have a full fridge there is less air in it and therefore less air can escape.
Top-opening-freezers are more efficient because of that. Cold air is more dense (heavier) than warm air. The cold air stays in the top-opening-freezer while it floats out of a front-opening-freezer.

World's Simplest Electric Train Jeson 14/12/23(Tue)20:30 No. 16007 ID: 3791e5 [Reply]

File 141936303681.png - (512.38KB , 1459x468 , baterija.png )

The trick in the video is that the magnets are made of a conducting material and they connect the battery terminals to the copper wire, so the battery, magnets and copper wire make a circuit that generates a magnet field just in the vicinity of the battery. The geometry means the two magnets are automatically at the ends of the generated magnetic field, where the field is divergent, so a force is exerted on the magnets.

The magnets have been carefully aligned so the force on both magnets points in the same direction, and the result is that the magnets and battery move. But as they move, the magnetic field moves with them and you get a constant motion.

If you flipped round the two magnets at the ends of the battery the battery and magnets would move in the reverse direction. If you flipped only one magnet the two magnets would then be pulling/pushing in opposite directions and the battery wouldn't move.

What you need:
1. Neodyum magnets
2. Dry cell battery
3. Copper wire

World's Simplest Electric Train Jeson 14/12/23(Tue)20:38 No. 16008 ID: 3791e5


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