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File system that stores location of file in Pi

github.com

11–20 of 102 posts

Re: File system that stores location of file in Pi

#11

I'm skeptical that this could really save any space. Just speculating here, really, but it seems like on average the amount of space needed to store the starting index of an arbitrary string of digits in pi should be greater than (or at least comparable to) the size of the string itself. e.g., the first instance of "256" in pi starts at the 1750th digit. So in that case you're getting a 'compression' rate of -33% if…

... and that's the joke.

Re: File system that stores location of file in Pi

#12

I'm skeptical that this could really save any space. Just speculating here, really, but it seems like on average the amount of space needed to store the starting index of an arbitrary string of digits in pi should be greater than (or at least comparable to) the size of the string itself. e.g., the first instance of "256" in pi starts at the 1750th digit. So in that case you're getting a 'compression' rate of -33% if…

You should really consider commenting on the project pointing this out to the author; I think he'll be disappointed to know that he hasn't discovered a way to magically compress random data.

That said, I wonder if "but remember all that storage space we saved by moving our data into π? Why don't we store our file locations there!?!" wasn't meant as some kind of hint...

Re: File system that stores location of file in Pi

#13

I'm skeptical that this could really save any space. Just speculating here, really, but it seems like on average the amount of space needed to store the starting index of an arbitrary string of digits in pi should be greater than (or at least comparable to) the size of the string itself. e.g., the first instance of "256" in pi starts at the 1750th digit. So in that case you're getting a 'compression' rate of -33% if…

Don't worry, it scales well!

Re: File system that stores location of file in Pi

#15
post #6

Earlier quoted context omitted.

Its also pretty obviously an elaborate mathematics joke.

Yes, but it conceivable. It's like a code. You could securely save files with two numbers. Just a position and length.

It would only be secure if nobody knows what the position refers to. And the position is likely to be longer than the data, so you might as well use proper encryption.

Re: File system that stores location of file in Pi

#17

I'm skeptical that this could really save any space. Just speculating here, really, but it seems like on average the amount of space needed to store the starting index of an arbitrary string of digits in pi should be greater than (or at least comparable to) the size of the string itself. e.g., the first instance of "256" in pi starts at the 1750th digit. So in that case you're getting a 'compression' rate of -33% if…

To be fair, it compressed my 93 Gb file into 6 bytes. Incidentally, the file stored the first 100 billion decimals of pi.

Re: File system that stores location of file in Pi

#18
Obligatory Dinosaur Comics: http://www.qwantz.com/index.php?comic=353

"You can't copyright a fact (like a number), but you can copyright a creative work, like a song or a piece of software. But since one can be transformed into another, copyright law is logically INCOHERENT."

Re: File system that stores location of file in Pi

#19

Obligatory Dinosaur Comics: http://www.qwantz.com/index.php?comic=353 "You can't copyright a fact (like a number), but you can copyright a creative work, like a song or a piece of software. But since one can be transformed into another, copyright law is logically INCOHERENT."

Godel's lesser-known Nonliability Theorem has as of yet failed to gain much traction in the MPAA.

Re: File system that stores location of file in Pi

#20
post #9
post #4

Earlier quoted context omitted.

I think it would probably take forever for the initial lookup, because the probability of matching any 3 byte sequence is higher than matching a 200 bytes sequence?

Literally forever, right? It's basically scanning a random byte-stream for a 200-byte long exact match. 200 bytes, 1600 bits, or 2^1600 different possible sequences, making the odds 1/2^1600 that any particular 200 bytes pulled out will match the bytes you are looking for.

In fact, it's still not known if pi is normal (contains all finite patterns of numbers[π]), so you can't guarantee that any search will terminate.

π: Not quite the definition of normal, but equivalent.

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