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Negative Base

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41–50 of 74 posts

Re: Negative Base

#41
post #9

I remember when negative zero was labelled a hoax. (-: * https://en.wikipedia.org/w/index.php?title=-0&diff=25603603&... * https://en.wikipedia.org/wiki/Wikipedia:Articles_for_deletio...

Best way to represent nil, in my opinion ;)

Although it smells like a design flaw (which negabinary conveniently doesn't have)

Re: Negative Base

#45
post #8

Earlier quoted context omitted.

I don't think anyone ever imagined a use for imaginary numbers either, but those turned out to be quite useful for reducing dimensionality. Towards the bottom of the article it states that Donald Knuth proposed imaginary base numerical systems. So this may eventually find a use, likely with higher-dimensional math.

It will be really funny if there is some bit of new, undiscovered physics, that went undiscovered for so long just because it's best described using some esoteric maths like complex base numbers. Highly unlikely, but fun to think about.

Are there any examples where the representation of a number matters in physics?

Re: Negative Base

#46
post #8

Earlier quoted context omitted.

It will be really funny if there is some bit of new, undiscovered physics, that went undiscovered for so long just because it's best described using some esoteric maths like complex base numbers. Highly unlikely, but fun to think about.

Are there any examples where the representation of a number matters in physics?

I recall some effort in moving from imperial measurement to metric. Reality itself does not care, but the math sure gets easier if you carefully select units.

Actually, another neat example is analog vs digital computation. your models can get very different answers. I recall some Mandelbrot guy talking about that.

Re: Negative Base

#47
post #5

Earlier quoted context omitted.

Well, the number of digits tell you the sign of the number, right? It could save a sign bit I think the ideal wikipedia page for this kind of thing has a 'Properties' section from which to start thinking about this

The bit saved for the sign is lost because you need more bits to represent a number.

True, and it seems you actually need exactly one extra bit for all positive numbers

Re: Negative Base

#49
post #37

Earlier quoted context omitted.

XVI ⨉ XXIII = XVI ⨉ (XVI + I) = (XVI ⨉ XVI) + XVI = CCLVI + XVI = CCLXXII

I didn't say that it wasn't computeable, only that I bet you couldn't do it in your head. Note that your calculation for some reason (EDIT: ah, maybe because my Arabic-numeral problem has 16 ⨉ 17?) replaces XXIII = 23 by XVII = 17, and then black-boxes the calculation XVI ⨉ XVI = CCLVI (which I at least wouldn't know without converting).

I agree. You can use the same algorithm for computing both. But Arabic has better constants. Because it's a discrete convolution instead of grouping and aggregating.

      1 6
    1 1 6
    7 7 42
    1, 6+7, 42 = 100 + 130 + 42 = 272
Same process in Roman

      X V I
    X C L X
    X C L X
    I X V I
    I X V I
    I X V I
    CC LL(=C) XXXXX(=L) VVV(=XV) III = CCCLXVIII = 16*23=368
This supports the arguments that Arabic numbers really are better suited for things like multiplying. They don't have the property that multiplication is convolution, so you can't even do things like truncate your computation to get an approximation.

There's probably a way to formalize this with an entropy argument: that roman numerals are inefficient encoding. Because given some n-length string of numerals, firstly many are invalid encodings, and secondly among the valid numerals there isn't a uniform distribution from strings to integers. Something like that.

Re: Negative Base

#50
post #40

Earlier quoted context omitted.

I'm going to have to take this riddle bait. My solution: Move 1: weigh 6 coins vs 6 coins. Isolate the heavier set for the next move. Move 2: weigh 3 coins vs 3 coins. Isolate the heavier set for the next move. Move 3: weigh any two of the 3 remaining coins. If one is heavier, that is the counterfeit. Otherwise (if coins are equal in weight) the remaining coin is counterfeit.

You failed because: > One is counterfeit and is either heavier or lighter It turned out the counterfeit was lighter and you discarded it after the first weighing.

Ahhhh... hmm. I thought it seemed too easy.
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