On Fri, Mar 07, 2003 at 02:48:34PM +1100, Tristan McLeay wrote:
>  --- "H. S. Teoh" <[log in to unmask]> wrote:
> > Well, doing stuff with other bases are very easy.
> > After all, base 8 is
> > just like base 10, if you're missing two fingers.
> > ;-)
> Indeed, but doing maths in Base 16 is a lot harder. In
> bases below 10, I can easily mentally switch into the
> base I'm learning, and it's plainly obvious to me that
> 7+1=10 (or 15+33=50). But it makes me so dizzy to add
> the extra six things to work in 16.

Hmm. I don't have much trouble with base 16... the only thing I stumble
over is the not-very-intuitive mapping of 10->A, 11->B, 12->C, etc.. I can
add/subtract/multiply hex numbers quite well, I just have to always think
twice before I know to write C for 12, D for 13, etc.. The main problem is
that I'm so used to A being 1, B being 2, etc., that the off-by-1 mapping
to 10, 11, 12, etc., just catches me off guard every time.

> (And no, I don't count on my fingers. I think with the digits on a piece
> of paper, but when doing something like 15+33, I would actually do
> (4+4)+(10+30).)

Hmm. I don't think in digits, I think in terms of the actual values the
digits represent. Now as for doing 15+33... you have a totally *bizarre*
way of doing it. :-) Why do you split it as 4+4 instead of 5+3?

> The *really* confusing thing, though, is is '15 base 16' fifteen,
> fifsixeteen /"fIfsaikstijn/, or twenty-one? (I like the middle one best,
> I think (no conversions needed but it won't cofuse you with fifteen),
> but its likely to greet me with blank stares.) Oh, and is 'one
> hundred'='100 base 10' or '100 base whatever' etc.?

I find the N. American convention of reading digits in pairs totally
bizarre and maggelitinous. (E.g., they pronounce "322" as "three
twenty-two". I'm used to just reading off the digits one by one, once
there are more than 2 digits. Of course, somehow the convention has
spread to my childhood in reading year numbers, so I'd read the year
"1992" as "nineteen ninety-two" but if it were just a quantity and not a
year number, I'd read the digits separately.) So from that perspective, I
read hex numbers by digits as well, so 10 base 16 is "one-zero", not
"ten", etc.. [*]

But I'm sure others would disagree with me. :-)

[*] Nevertheless, sometimes I take perverse pleasure in reading hex
numbers like 4B as "forty-B" and E5 as "Ety-five". :-P This is only when I
feel like deliberately speaking in riddles, though. Nothing like saying
"there are B-hundred twenty-F pixels in that window" and getting all those
blank stares. :-)


A computer doesn't mind if its programs are put to purposes that don't match
their names. -- D. Knuth