Byte help

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Summary:

Is there a way?

Byte help

jnesselr 02 Jan 2009 15:13

Is there a way to take three bytes, A, B, and C, that all have values between 0 and 255, and turn them into two bytes, with the values between 0 and 255, while maintaining the ability to recall numbers A, B, and C.

For example, if I where to have Bytes A, B, and C, and I where to apply a formula to them, I would get D and E. If I told you D and E, could you figure out A, B, and C, given the formula?

I need the formula, that can turn 3 bytes, into 2 bytes, and then, back to 3 bytes. Any help would be appreciated.

Re: Byte help

builderboy 02 Jan 2009 17:29

Its just not possible. Consider all the scenarios, with 3 bytes, that is 256*256*256 (16,777,216) possible scenarios. With 2 bytes you can only represent 256*256 (65536) different scenarios. Its not nearly enough to get back all three original bytes.

Last edited on 02 Jan 2009 17:30 by builderboy Show more

Re: Byte help

jnesselr 02 Jan 2009 18:41

Sadness fills my heart.

Re: Byte help

calccrypto 02 Jan 2009 19:06

maybe this might help.
look for the chart that says

Text content

M

a

n

---

Visit Calccrypto for info on crypto
KC2ZOF

Re: Byte help

simplethinker 02 Jan 2009 20:09

There's no way to store the data, much less extract it. If you have A=255, B=254, C=253 then how could they be combined into a 2-byte number? Just adding them puts them past 65535.

Re: Byte help

seb83 09 Jan 2009 00:14

can your number have decimals ?

Re: Byte help

seb83 09 Jan 2009 00:17

because you could say

a/100 + b → d
c → e

and then after,

100 fPart(d → a
iPart(d → b
e → c

Re: Byte help

jnesselr 09 Jan 2009 00:28

bytes, only. Numbers between 0 and 255 only, no decimals.

P.S. if you want to edit a post, click options, then edit.

Re: Byte help

simplethinker 09 Jan 2009 13:25

A byte is an integer 0-255. The reason for 255 is that computers store information in bits (binary digits), groups of four bits are called "nibbles", which are the hexadecimal numbers 0-F. Two nibbles together are 0-FF, which in decimal is 255. This means that 16 bits=2 nibbles = 1 byte can be represented as hex numbers 0-255. What you were thinking of were Floating-point numbers, a description of which can be found in (1) of this post.

Hope this helps :)

Re: Byte help

darkstone knight 09 Jan 2009 13:35

depending on the way you code stuff, an intriger represents an number between P and Q, whit each X(n) being (P-Q)/256 larger than X(n-1)

notice this becomes hela confusing if you take numbers like -7 and 203..

EDIT: errr… byte..

Last edited on 09 Jan 2009 15:42 by darkstone knight Show more

Re: Byte help

seb83 10 Jan 2009 03:09

thanks