# Re: On writing negative zero - with or without sign

James Giles writes:

....

In simulating continuous reals, there are no exact zeros.

You keep repeating the same claim, but you don't offer any proof
of that claim. Do you deny that a subset of continuous reals
can be represented exactly with a finite number of bits?

Do you deny that a discrete subset of the continuous reals is
discrete?

I see that you didn't answer my question.

A property of a subset isn't necessarily a property
of the whole set.

A member of a subset is a member of the whole set. Is zero a
member of that subset?

Reals aren't discrete even though quite a
few differntly defined subsets of the reals are discrete.

Is zero a member of a discrete subset?

That's relevant because exactitude in computing is only
possible on discrete sets.

We're not talking about exactitude in general. We're talking
about the existence of an exact zero.

When simulating continuous sets
yuo have no exactitude.

So whenever the topic becomes whether pi is exact or not, you
can raise that point. But the issue is zero, not pi.

In simulating continuous reals there
are no exact numbers, zeros or otherwise.

I disagree. Consider the subset of reals that can be exactly
represented. I zero a member of that subset?

Well, you're now getting abusive as well.

Classic unsubstantiated and erroneous claim.

I have no interest in further proving you wrong.

Classic erroneous presupposition that you've proved me wrong.

No doubt you'll claim I've done no such thing.

With good reason.

In fact, nothing you've said is even slightly interesting,

On the contrary, you've been interested enough in what I've said
to keep responding for several days, several times per day.

much less convincing that anything I've said is wrong.

If you want to go through life thinking that there's no way for
a processor to represent an exact zero, that's your choice, Giles.

.

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