Just a note to Apple Geniuses, there is no such number as "-0". Just saying.

[Augiedog]

My watch, Apple Watch, this morning displayed -0 as a temperature. In no form of math is -0 a number, real or otherwise.

Obviously this is an incredibly important issue so I expect intense reaction and debate. Please be courteous as I am very sensitive and easily offended…kinda like contemporary republicans and your average next door neo nazi, and proud boy(s). Uncapitalized intentionally.

Note: I would have included a photo of my watch making the offending offering of -0 but I can’t figure out how to include the pic from my photos. Maybe more coffee is required, or less.

[Beetwasher.]

1. I Blame Science

And Fauci.

[Haggard Celine]

3. Fauci is the Antichrist.

He is the source of all erroneous and evil things.

[WhiskeyGrinder]

2. That's called a signed zero and if the actual temperature is -.4, the app rounds it but keeps the

sign.

[stopdiggin]

4. I learned something (early) today -(nt)-

[Klaralven]

5. -0 can be represented in sign-magnitude, one's complement and signed decimal notations

https://en.wikipedia.org/wiki/Signed_number_representations

https://en.wikipedia.org/wiki/Binary-coded_decimal

[targetpractice]

6. Blasphemer! n/t

[Emile]

7. I call it zero, my wife calls it oh, who is right?

[lagomorph777]

21. It's "negative naught"

[Beastly Boy]

8. Outrageous! This is a slippery slope, leading to the end of math as we know it.

What's next, representing Pi with only four digits after the decimal point and ignoring the rest? Imagine what it will do to humanity's conception of infinity, with all its devastating implications on philosophy and religion, among a multitude of other fundamental disciplines.

[lastlib]

10. This could truly be the first sine of insanity.....

We must not go down this road.......

[localroger]

16. Yeah, we might end up on a tangent /nt

[lagomorph777]

22. Come on, you're being hyperbolic.

[lastlib]

25. It's our function.

All these puns have only imaginary humor, and zero real value.

[Lucky Luciano]

26. This is very complex!

Trying to figure out how to upgrade the pun to use Quaternions…and failing.

[mitch96]

9. I had a discusssion about this with a friend and some fine Porter..

His rational is that "0", zero is a place holder. There for it is a negative space....
I disagreed but he was happy YMMV

m

[genxlib]

11. In my book

If the temperature is 0, then you have bigger things to worry about.

[Miguelito Loveless]

12. You've heard of "imaginary numbers"?

-0 is a "psychotic number".

[dsc]

13. yes there is

it is the number I give as a grade to a student who really p's me off.

[TreasonousBastard]

14. And the square root of - 0 is swimming around with cube root.

[MineralMan]

15. My digital weather station shows tenths of degrees.

So, 0 degrees is normally signed + or -, depending on the tenths value. I can't remember what it shows if it is exactly 0 degrees. I may never have seen that, actually.

The Apple Watch knows what the tenths value is, but doesn't display it. So, it assigns the correct sign, instead, I suppose.

Today, at 7 AM, the outside temperature was -14.3 degrees Fahrenheit. It might reach 2 degrees later today. It is damned cold out there. What I say when the temperature is 0 degrees is that there is no temperature.

[NutmegYankee]

17. My weather station does that when rounding.

The detail view shows -0.2°, but the basic display will show -0.

[MineralMan]

20. There are also plus tenths of a degree.

So, -0.5 degrees and +0.5 degrees are both valid temperature measurements, with a difference of 1 degree between them.

The first is half a degree below 0 and the second is half a degree above zero.

It doesn't really matter of course. Both are damned cold and tenths of a degree are relatively useless as measurements, except on fever thermometers.

[localroger]

18. Minus zero is a possible value in all common floating point representations

One usually rounds the minus away before displaying the result. There are other oddities to floating point, for example the fraction 1/10 is infinitely repeating in binary (as 1/3 is in decimal) so that if you don't round the result, 1 / 10 * 10 = 0.9999999... which was a result some early computers would return. These quirks are why some systems have a special representation for values of money so that accounts will add up correctly.

[Lucky Luciano]

19. Correct! Saved me the typing!

[Retrograde]

23. Back in the olden days

before Microsoft killed OS research, when MS DOS was barely a glint in Bill Gates' eye, there was a computer company called Control Data Systems. Their instruction set had both a positive and a negative zero. I don't remember why.

But there is no excuse for Apple. And while you're at it, tell them there is no such thing as the Cupertino Time Zone: the normal people who live there call it Pacific Time.

[localroger]

24. sign-magnitude and one's complement

Let's say we have a 4-bit register consisting of a sign bit and the bits for binary values 4, 2, and 1. +5 decimal would be 0101. But in sign-magnitude, the sign bit would flip to represent -5 as 1101. But math is complicated in sign-magnitude because a lot of operations are necessary to deal with opposing sign bits. So some companies used one's complement, where the sign bit would indicate that the other bits are all inverted, so -5 would be 1010. You still have to check for sign crossings, but you don't have to do an inversion when you find one. Both of these systems have minus zero as a possible value which must be detected in math.

Most modern CPU's use two's complement though, where the inverted bits are incremented. So in two's complement -5 would start by inverting 0101 to 1010, then add 1 to get 1011. We can show that this is minus five by incrementing it: -5=1011 < -4=1100 < -3=1101 < -2=1110 < -1=1111 < 0=0000. In this representation addition and subtraction are the same regardless of whether the most significant bit is a sign bit or not, and there is no minus zero.

Floating point math, used by nearly all modern computers for numbers that can contain fractions, is a variation on sign-magnitude which adds an exponent and sign bit to a positive integer mantissa. FP math is complicated anyway and has a number of other speed bumps; not every binary bit pattern is a valid FP number. But with modern computers being so fast it's very common to see it used even when it's not really necessary, as in temperature calculations.

[themaguffin]

27. Why is this in this forum???