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Started by Stupot, Fri 19/12/2008 20:06:21

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Gilbert

I've never looked up for details, so the following are just what I understand from my experience:

I think the adoption of hexadecimal is just natural (obviously much more natural and mathematical than the denary system humans use most of the time, which is familiar to us mainly only because we were born with 10 fingers).

The smallest integral base for displaying numbers is 2 obviously, so binary representation of numbers is the basis of all basis, and since digital circuitries are just collections of on/off(logic) "switches" this is of high importance.

Of course, numbers displayed in binary are clumsy and inconvenient most of the time (except some cases like displaying flags), so we usually show numbers in certain bases that are easily converted to and from binary. In general, if the base is of the form 2^n the conversions are super easy, so leaving us with 2, 4, 8, 16, 32, 64, 128, 256, ... as possible bases.

Bases of 2 and 4 are obviously too clumsy for everyday use, and numbers displayed in base 32 and onward would require a large set of numerals (e.g. under base 32 you need 32 distinct symbols to represent a digit) and are inconvenient, so octal and hexadecimal representations of numbers are optimal.

Both octal numbers and hexadecimal numbers are widely used, but in many cases hexadecimal is preferred, because:
1. It takes 4 bits to represent a hexadecimal digit (16 = 2^4). In general it's more organised if the number of bits in a group is also an even power of 2 (4 = 2^2), compared to octal numbers where each digit composes of the odd 3 bits.
2. While for octal numbers you only need 8 distinct symbols in the set of numerals to display any number (i.e. we can just directly use 0-7 from the denary digits), you need 16 symbols in hexadecimal (most of the time we use the 0-9 denary digits together with the six Roman letters A-F). However, hexadecimal numbers are more compact that we never need to use more places to represent a number compared to it represented with our everyday denary system.
3. This is an extension of 2, as humans use denary numbers in their everyday life, it may be sometimes convenient (for our eyes) to just use a hexadecimal digit to display a denary digit, e.g. we use the hexadecimal number $99 to represent the denary 99. In fact, the 6502 family of CPUs had a BCD mode that, when set, would treat each byte as a denary 2-digit number and could do (only limited) decimal arithmetic directly. Few people really used this mode though (and when Nintendo and Ricoh cloned the 6502 core for their Famicom they even removed this ability, though from what I've heard this was mainly due to patents). This is not possible with octal numbers, as each digit can only be 0-7, which is not enough to represent a denary number directly.

InCreator

#201
Ugh. This makes me dizzy.

But even while I don't see how using numbers that result in answer to a calculation instead of simple units (like hexadecimal F means base of something blah blah complex but decimal 10 means simply 10 apples or coins) useful in "real life", I think I understand how it's useful on paper (or rather - as digital data)... but, we don't use hexadecimal in everyday life anyway.

Still, I will die not fully understanding hexadecimal.

bicilotti

Quote from: InCreator on Wed 09/12/2009 11:21:17
Ugh. This makes me dizzy.

But even while I don't see how using numbers that result in answer to a calculation instead of simple units (like hexadecimal F means base of something blah blah complex but decimal 10 means simply 10 apples or coins) useful in "real life", I think I understand how it's useful on paper (or rather - as digital data)... but, we don't use hexadecimal in everyday life anyway.

Still, I will die not fully understanding hexadecimal.

Just one quick thought on the base thing: 25 minutes + 40 minutes are... 1 hour and 5 minutes  :P

Bases different than 10 (or even something more complex, like day/hour/minute thing) are really just a matter of being used to.


Scarab

Quote from: bicilotti on Wed 09/12/2009 18:44:46

Just one quick thought on the base thing: 25 minutes + 40 minutes are... 1 hour and 5 minutes  :P

Bases different than 10 (or even something more complex, like day/hour/minute thing) are really just a matter of being used to.


Yeah, I always wondered what it would be like if we used a base-12 counting system. Fractions like 1/3, 1/4, 1/6 and 1/9 would become really nice, clean numbers and mental maths would become just that little bit easier.

Also, for us to develop this system naturally would likely mean six fingers on each hand, which would be interesting... ;D

bicilotti

#204
Quote
Yeah, I always wondered what it would be like if we used a base-12 counting system. Fractions like 1/3, 1/4, 1/6 and 1/9 would become really nice, clean numbers and mental maths would become just that little bit easier.

Also, for us to develop this system naturally would likely mean six fingers on each hand, which would be interesting... ;D

Duodecimal(sp) is pretty handy when it comes to divisions or plain quotients, since it has many divisors. Many "regional" units of measure use it for this simplicity (1 imperial foot = 12 inches, for example, or the italian dozzina), before decimalisation.
If modern and cheap calculating machines weren't available, I would be for sure an advocate of this numeral system as the main one.

Getting back on topic, here's the wiki page on the Suanpan. It's a very simple and elegant eastern abacus: when I was I kid I learned to use it for decimal calculations, but it can be used for hexadecimal calcs too.
It seems that chinese weighting units were hexadecimal at the time, so their abacus was built that way.
I still don't know why they chose hex over duodecimal, since the latter has a 3 divisor as a bonus.

InCreator

Quote from: bicilotti on Wed 09/12/2009 18:44:46
Just one quick thought on the base thing: 25 minutes + 40 minutes are... 1 hour and 5 minutes  :P

Bases different than 10 (or even something more complex, like day/hour/minute thing) are really just a matter of being used to.

Matter of being used to - yes
Comfortable - no

Gilbert

It's because we're used to count in group in 10 when we're small (and our commonly used symbols). If we were born in a place that counting is done in another base it wouldn't be uncomfortable at all.

Andail

Many languages have up to twelve "original" names for numbers, and then start combining the name parts for 13 and upwards, which may indicate some sort of early idea of implementing a base 12 system.
If it wasn't for this fact, the "teens" would start at eleven...

Jim Reed

Wiki qoute:

"Most computers manipulate binary data, but it is difficult for humans to work with the large number of digits for even a relatively small binary number. Although most humans are familiar with the base 10 system, it is much easier to map binary to hexadecimal than to decimal because each hexadecimal digit maps to a whole number of bits."

I'd say this is why we use it, but it's just my opinion.
Also, Croatian doesn't have "original" names like eleven and twelve, but use 'teens for those numers instead. But, Croatian isn't many languages anyway =P.

Also, I'm looking for a very old Spectrum game, which revolves around two ships (a pirate and a french one) having a close combat fight. I can remember that the game is about two captains commanding their sailors across a net hung between theese two ships. The game is turn-based. If anyone can help me with this I'd be much obliged.

m0ds

Yo! Sorry, a slightly mundane question:

What's the best way to back up all your Outlook emails?

I've had some PC issues...since I've ever had a PC...and I keep losing all of them :(

I feel more guilty now than ever because there were quite a few un-answered emails and I'm not sure if I will ever see those old emails again. If anyone has personal experience of this and can advise me on good practices to back up emails, whether I can retrieve certain old data from a server or what not, let me know! And many apologies if you emailed me recently. You'll never get a reply :( :P

InCreator

#210
huh?

http://email.about.com/od/outlooktips/qt/Back_Up_or_Copy_Outlook_Data.htm

Also, fresh installs of Outlook tend to delete mail from server whenever received. I had quite a trouble with this: Checking work mail at home, seeing that I'd been sent some design drawings - and next day at work, there's no mail, no drawings, so I had to go back home and retrieve drawings!

There's a check button to "keep messages in server" but it's buried under loads and loads of "settings" and "advanced" window trees.
Shame on microsoft making this so retarded.

Question!

I see GIF files. 256-color, animated, from 1987.

It's 2010 soon. Where's a modern animated image format -- with 24-bit color and alpha channel?
Is there one? I mean, something usable, readable by any browser, etc?

If not, why???...!

Crimson Wizard

Quote from: InCreator on Wed 23/12/2009 16:48:21
Question!

I see GIF files. 256-color, animated, from 1987.

It's 2010 soon. Where's a modern animated image format -- with 24-bit color and alpha channel?
Is there one? I mean, something usable, readable by any browser, etc?
Umm... flash video?  ;D

Calin Leafshade

MNG is the format youre looking for.. though it has yet to gain widespread use.

As an aside GIF images are capable of full colour.. They are not limited to 256 colours.

InCreator

#213
Ok, thanks. I guess it's quite useless as wikipedia article describes it's failure to become important and lack of support. I was actually just wondering, why don't we still have something that's 10+ years late.

More serious question!

Is there something that creates connected vectors with endpoints, and I can link vectors-points and assign images to them so I have something to create animations simply?

I mean something exactly like SSH's walkcycle generator, but with more options and power?
Flash... feels a bit too complicated for such little task.

Babar

You could try MOHO.

http://www.lostmarble.com/

Ohwell...it appears it is called Anime Studio now. Should still be a breeze to work with, though. I still have an ancient copy of it.

It costs moneys, but it has a free evaluation (which I think leaves a watermark :( )
The ultimate Professional Amateur

Now, with his very own game: Alien Time Zone

InCreator

#215
Pity it has most anal way to get a trial, ever  :(

Edit: This program is absolutely awesome. thanks!

Bulbapuck

#216
*Solved and removed due to taking up all that space :P*

Dualnames

#217
Quote from: InCreator on Wed 23/12/2009 21:24:16
Ok, thanks. I guess it's quite useless as wikipedia article describes it's failure to become important and lack of support. I was actually just wondering, why don't we still have something that's 10+ years late.

More serious question!

Is there something that creates connected vectors with endpoints, and I can link vectors-points and assign images to them so I have something to create animations simply?

I mean something exactly like SSH's walkcycle generator, but with more options and power?
Flash... feels a bit too complicated for such little task.

Steve and SSH, worked on something like that. Check the Thread about Walkcycle Generator there's a download link on page 5 if I recall.

EDIT:

Here..
http://www.adventuregamestudio.co.uk/yabb/index.php?topic=26501.msg421043#msg421043
Worked on Strangeland, Primordia, Hob's Barrow, The Cat Lady, Mage's Initiation, Until I Have You, Downfall, Hunie Pop, and every game in the Wadjet Eye Games catalogue (porting)

Bulbapuck

#218
I'm sorry about double posting here... But the reason is that I'm at school and I can't go home until I finish this. And I'm getting hungry...

I added "pack();" at the end of the frame's constructor. Now the size isn't zero, but it's very small. Almost as if my "setSize" in the panel's constructor is being ignored.

Help!

EDIT: This is solved, need no help.

Oliwerko

Could anyone possibly tell me what keyboard synth is played in Phil Collins's "I don't care anymore" ?

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