From: Harry Potter on
I need to be able to calculate the logarithm to base 2 of a number,
but I am limited to a high school education. I am working on some
complex file compression techniques. I also want powers, roots,
exponents and logs for another time.
From: Joe Forster/STA on
On Jul 2, 5:05 pm, Harry Potter <maspethro...(a)aol.com> wrote:
> I need to be able to calculate the logarithm to base 2 of a number,
> but I am limited to a high school education.  I am working on some
> complex file compression techniques.  I also want powers, roots,
> exponents and logs for another time.

http://en.wikipedia.org/wiki/Logarithm etc.
From: Maciej Witkowiak on
Harry Potter wrote:
> I need to be able to calculate the logarithm to base 2 of a number,
> but I am limited to a high school education. I am working on some

For integer arithmetics, it can be found very easily:
floor(log_2(n))+1 is equal to the number of bits needed to store n. Basically
it is the position of the last '1' in binary representation of n when counting
from right to left.
E.g. for n=14 you need 4 bits to store that number and the value of log_2(14)
is somewhere in (3,4) interval.

If you would need precise answer, for whatever reason, then:
log_2(n)=ln(n)/ln(2)

> complex file compression techniques. I also want powers, roots,
> exponents and logs for another time.

Then you need to find ln() and exp() implementations, those functions can be
combined to calculate powers and roots.

ytm

--
Najlepsza sygnatura to brak sygnatury.
http://bossstation.dnsalias.org/
From: Harry Potter on
On Jul 3, 5:38 am, Maciej Witkowiak <y...(a)elysium.pl.andremowe.me>
wrote:
> Harry Potter wrote:
> > I need to be able to calculate the logarithm to base 2 of a number,
> > but I am limited to a high school education.  I am working on some
>
> For integer arithmetics, it can be found very easily:
> floor(log_2(n))+1 is equal to the number of bits needed to store n. Basically
> it is the position of the last '1' in binary representation of n when counting
> from right to left.
> E.g. for n=14 you need 4 bits to store that number and the value of log_2(14)
> is somewhere in (3,4) interval.
>
> If you would need precise answer, for whatever reason, then:
> log_2(n)=ln(n)/ln(2)
>
> > complex file compression techniques.  I also want powers, roots,
> > exponents and logs for another time.
>
> Then you need to find ln() and exp() implementations, those functions can be
> combined to calculate powers and roots.
>
> ytm
>
> --
> Najlepsza sygnatura to brak sygnatury.http://bossstation.dnsalias.org/

Thank you, both of you!