OpenEuphoria

RE: String compression

• Posted by Brian Broker <bkb at cnw.com> Dec 16, 2003
• 443 views

If anybody was so concerned about string storage to implement such a 
scheme I'd tell them it's time to upgrade their system or start 
programming in lower level language...  Did you know you can buy a 512MB 
stick of PC100 RAM for less than $50?  That's less than 10 cents per 
Meg.  If I did my math right, that's over 31,000 characters per penny 
using a plain old sequence.

Just a thought,
-- Brian

Hayden McKay wrote:
> I noticed that people were concerned about string memory usage so I came 
> up with this.
> To my knowlege an integer is stored as an integer regardless
> of its length, (since computers store such things in binary).
> Please correct me if I'm wrong. 
> Its not much but a good start, modify it as u see fit.
> 
> include machine.e
> -- integer = p_ints(integer digit, integer digit)
> -- Pack two integers onto one integer.
> -- Returns a single integer.
> global function p_ints(integer a,integer b)
> sequence s
> atom n
>    s = int_to_bits(a,16)
>    s &= int_to_bits(b,16)
>    n = bits_to_int(s)
>    return n
> end function
> -- sequence = u_ints(integer digit)
> -- Unpack integer into two integers.
> -- Returns a double integer sequence.
> global function u_ints(integer n)
> sequence s
> object a
>    s = int_to_bits(n,32)
>    a = bits_to_int(s[1..16])
>    a &= bits_to_int(s[17..32])
>    return a
> end function
> 
> I have another routine that compresses whole words into an integer, but 
> since two different words can equal the same integer I run into problems 
> reversing it. (it only works for certain words about 5 - 10% of the 
> time). 
> (95% of the time I get different run_time errors.)
> I have three theorys to over come this.
> 1. Store a digit on the end as a seed to reversing the word.
> eg: the length of the word.
> 2. Compress word to a decimal atom to contain a seed in itself.
> 3. It cannot be done!
> 
>  If any one knows were I can find related topics it be much helpfull.