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Entropy

andrew-hoyer.com

21–30 of 32 posts

Re: Entropy

#21
post #17

Earlier quoted context omitted.

Computers are inherently imprecise? Floating point is imprecise, yeah lets generalize that to the entire computer..

Float operations are actually precise, the catch is that floats are not real real numbers.

Is there any part of a computer that could actually be considered imprecise? Perhaps only if there is a hardware malfunction.

Re: Entropy

#22
post #17

Earlier quoted context omitted.

Float operations are actually precise, the catch is that floats are not real real numbers.

Is there any part of a computer that could actually be considered imprecise? Perhaps only if there is a hardware malfunction.

You could argue that float/int arithmetic is inherently imprecise. It is, however, fully deterministic.

Of course as you hint in your comment, at a lower level hardware is prone to failures and lack determinism: bugs in the cpu, ram corruption (ECC-ram is of course better), data corruption everywhere on storage/network/data links, etc. Ever heard a gamer bitching about Windows 7 instability? That's not Windows, but overclocking not quite under control and/or insufficient cooling...

And when all is under control a cosmic ray might still wreak your bits havoc.

Re: Entropy

#23
This reminds of the polymorphic viruses in MS-DOS/Windows era (very likely they still exist, but I didn't look for long time) where they would dynamically generate the decryption/encryption routines and changed their code appearances to thwart signature-based antivirus scanners. As such, maybe it would be fun to add self-modifying codes so that 1) precision is reduced 2) performance is also randomly reduced. The longer you run this baby, the slower and less precise it would be. ;)

Re: Entropy

#24
post #17

Earlier quoted context omitted.

Float operations are actually precise, the catch is that floats are not real real numbers.

Is there any part of a computer that could actually be considered imprecise? Perhaps only if there is a hardware malfunction.

It's deterministic at some level, but can be very difficult to predict when a compiler will decide to spill 80-bit float registers to 64-bit doubles in memory.

Re: Entropy

#25

This reminds of the polymorphic viruses in MS-DOS/Windows era (very likely they still exist, but I didn't look for long time) where they would dynamically generate the decryption/encryption routines and changed their code appearances to thwart signature-based antivirus scanners. As such, maybe it would be fun to add self-modifying codes so that 1) precision is reduced 2) performance is also randomly reduced. The long…

> very likely they still exist

Sadly. They're one of the more complex malware types.

Re: Entropy

#26
post #18

I see an evil DRM for games, you buy a game and textures will decay over time until you buy the game again to reset the decay.

Back in the day, AutoCAD did that with point coordinates. No dongle, each save got progressively worse.

Did you mean 3D Studio on DOS?

Re: Entropy

#27
post #26
post #18

Earlier quoted context omitted.

Back in the day, AutoCAD did that with point coordinates. No dongle, each save got progressively worse.

Did you mean 3D Studio on DOS?

AutoDesk not AutoCAD! gah. I think you're right.

There was a collection of DRM stories i read a few years ago. People (businesses, architects, professionals that should know better) calling for tech support over corrupted files was memorable (but apparently not memorable enough). I imagine there was some grim joy in informing people they were not using a legitimate copy, and thus their program was failing.

Re: Entropy

#28
Computers are precise but sometimes I wonder could they be made faster if we relaxed this precision requirement?

For example in game 3d graphics it might acceptable to sacrifice some precision for performance. Could be interesting to apply some thing "Entropy" to the graphics part of some existing game. Flappy Bird maybe?

Re: Entropy

#29
post #2

It would be interesting to write a program that is going to work properly by using only such "decaying" variables. There are actually applications for such programs - software replacement for ECC memory.

I thought you were about to go full thermodynamics on the data and suggest building an information-equivalent of the Stirling engine.

Re: Entropy

#30

Computers are precise but sometimes I wonder could they be made faster if we relaxed this precision requirement? For example in game 3d graphics it might acceptable to sacrifice some precision for performance. Could be interesting to apply some thing "Entropy" to the graphics part of some existing game. Flappy Bird maybe?

The speed/precision trade-off in games is well known and exploited to the max by those that care.
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