Re: converting numbers

[David Stern <dstern@u.washington.edu>]

On Thu, 28 Jan 1999 12:17:34 CST, Andrew Ivanov wrote:
> > Howdy,
> > 
> > Where's the FM that tells how to convert numbers, like 0x11A to a 
> > "decimal"?
> 
> 0x11A is in hex, and to convert it to dec is
> 1*16^2 + 1*16^1 +10*16^0
> (A=10,B=11, C=12, D=13, E=14, F=15)

I should never have asked this question before having some coffee. :-)

> I may be wrong, but I think octal is in x0# format, so that 
> 0x0300 would be an octal number.
> To convert that to dec is
> just 3*8^2+0*8^1+0*8^0, and ignore the leading 0 after x, which is used to
> idenbtify the radix.

OK, hex numbers are radix 16, octal radix 8, decimal radix 1.

So, a leading "0x" indicates hex, and a leading "0" traditionally 
indicates octal, although the latter may require contextual information 
to distinguish between decimal, which should not be written with a 
leading zero, if I read Henning Makholm correctly (thanks Henning!), 
and I'll disregard the mention of binary.

Good.  Now I can convert between hex, octal and decimal.  

I guess I'll have to determine when to use each based on context.

Thanks!  Now, where is that coffee? :-)
-- 
David
dstern@u.washington.edu