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1 kilobyte is precisely 1000 bytes?

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Re: 1 kilobyte is precisely 1000 bytes?

#351

Post by fc417fc802 »

purplehat_ wrote: post #296
fc417fc802 wrote: post #253

Earlier quoted context omitted.

> I don't think of base 10 being meaningful in binary computers. They communicate via the network, right? And telephony has always been in base 10 bits as opposed to base two eight bit bytes IIUC. So these two schemes have always been in tension. So at some point the Ki, Mi, etc prefixes were introduced along with b vs B suffixes and that solved the issue 3+ decades ago so why is this on the HN front page ?! A better…

To be fair, the octet as the byte has been dominant for decades. POSIX even has the definition “A byte is composed of a contiguous sequence of 8 bits.” I would wager many software engineers don't even know that a non-octet bytes were a thing, given that college CS curricula typically just teach a byte is 8 bits. I found some search results about Texas Instruments' digital signal processors using 16-bit bytes, and cam…

I wanted to reply with a bunch of DSP examples but on further investigation the ones I checked just now seem to very deliberately use the term "data word". That said, the C char type in these cases is one "data word" as opposed to 8 bits; I feel like that ought to count as a non-8-bit byte regardless of the terminology in the docs.

NXP makes a number of audio DSPs with a native 24 bit width.

Microchip still ships chips in the PIC family with instructions of various widths including 12 and 14 bit however I believe the data memory on those chips is either 8 or 16 bit. I have no idea how to classify a machine where the instruction and data memory widths don't match.

Unlike POSIX, C merely requires that char be at least 8 bits wide. Although I assume lots of real world code would break if challenged on that particular detail.

Re: 1 kilobyte is precisely 1000 bytes?

#353

Post by tim333 »

highhedgehog wrote: post #315
Syzygies wrote: post #241

Earlier quoted context omitted.

He probably uses Phillips head screws.

wait, what is wrong with that?

Dunno but there are two similar but slightly different cross head screw designs https://www.pbswisstools.com/en/news/detail/phillips-and-poz...

Re: 1 kilobyte is precisely 1000 bytes?

#355

Post by fc417fc802 »

nayuki wrote: post #288
fc417fc802 wrote: post #283

Earlier quoted context omitted.

Oh. Indeed you're correct. I was thinking in computer terms instead of scientific terms. Personally I see this as reinforcing that computers as a context wouldn't really benefit from using "proper" SI. Note that no one is going to confuse mB for millibytes because what would that even mean? But also in practice MB versus Mb aren't ambiguous because except for mass storage no one mixes bytes with powers of ten AFAIK.…

> no one is going to confuse mB for millibytes because what would that even mean? Data compression. For example, look at http://prize.hutter1.net/ , heading "Contestants and Winners for enwik8". On 23.May'09, Alex's program achieved 1.278 bits per character. On 4.Nov'17, Alex achieved 1.225 bits per character. That is an improvement of 0.053 b/char, or 53 millibits per character. Similarly, we can talk about how many…

Touche! I had no idea that term was in use. That said, I remain unconvinced that there is any danger of confusion here. Benchmarking compression algorithms is awfully specific; it's normal for fields to have their own jargon and conventions.

> Just because you don't see a use for mB doesn't mean it's open for use as a synonym of MB.

At the end of the day it's all down to convention. We've never needed approval from a standards body to do something. Standards are useful to follow when they provide a tangible benefit; following them for their own sake to the detriment of something immediately practical is generally a waste of time and effort.

I don't believe I hallucinated unit notations such as mB and gB. Unfortunately I don't immediately recall where I encountered their use.

> In case you're wondering, mHz is not a theoretical concept either.

Just to be clear, I was not meaning to suggest that non-SI prefixes be used for quantifying anything other than bits. SI standardized prefixes are great for most things.

Re: 1 kilobyte is precisely 1000 bytes?

#356

Post by fc417fc802 »

tiagod wrote: post #323
fc417fc802 wrote: post #270

Earlier quoted context omitted.

It's odd though. Metric prefixes are always lower case, so GB isn't valid metric. Further, outside of storage manufacturers attempting to inflate their numbers when does is ever make sense to mix power of ten with 8 bit bytes? Networking is always in bits per second, not bytes. Edit: Disregard the metric bit but I think the rest still stands.

I don't understand what you mean. kA is a perfectly valid SI unit.

I don't understand what you don't understand. Where did I object to kilo-amperes?

Re: 1 kilobyte is precisely 1000 bytes?

#357

Post by kalaksi »

PostOnce wrote: post #342
kalaksi wrote: post #289

Earlier quoted context omitted.

> Same with pounds, for example. A pound is 16 ounces, which can be divided 4 times without involving any fractions. Try that with metric. Not sure if you're actually serious... 1 kg is 1000 g, dividing with 4 gets you 250 g, no fractions. And no need to remember arbitrary names or numbers for conversions. > Then there's temperature. Fahrenheit just works more naturally over the human-scale temperature range without…

re: fahrenheit, it's utility is that 0 and 100 are near the extremes of human comfort. 0 = fuckin cold and 100 = fuckin hot Whereas in C, 0 is fine and 100 means you died 50 degrees ago. However, C is much more useful in industry, where boiling and freezing points are more important.

Ah, I see. Though, it's still useful that the relevant range isn't 0-100 but can go below zero since it's a significant change in weather conditions when we're below freezing point, but I get your point.

In the end, it's probably what one is used to. Temperatures here are typically between -20'C and +30'C.

Re: 1 kilobyte is precisely 1000 bytes?

#358

Post by fuzzfactor »

defrost wrote: post #302
_0ffh wrote: post #299

Earlier quoted context omitted.

> Celsius also aligns well with Kelvins without fractions (unlike fahrenheit). But Fahrenheit aligns well with Rankine without fractions (unlike Celsius). [Imagine some symbol here indicating humour.]

I chuckled ... and yet remain on side with Celsius.

Fahrenheit has finer granularity without fractions.

IOW each Celsius degree is bigger than each Fahrenheit degree.

Even though the F numbers are so much higher and it seems unbearably hot :)

So for a thermostat that only can be set in 1 degree increments (without a decimal point), you have finer control when using F than using C.

Anybody can memorize the conversion more easily by throwing out the math, using table lookup -- made easier by throwing out most of the table too.

Just remember every 5 C equals a non-fractional F.

And every 5 C equals 9 F.

If all you are interested in is comfort level it's like this:

   C   F
  
   0  32
   5  41
  10  50
  15  59
  20  68
  25  77
  30  86
  35  95
  40 104
Least significant digit of F drops by 1 every time without fail.

Looks like it increases by 1 each time in the tens column, but it's only 9 so 50 & 59 are the outliers, which most people have memorized already.

If you are a Celsius native and you think in terms of 10, 15, 20, 25, 30 -- you only need to remember 5 different F numbers, 50, 59, 68, 77 & 86 and that will get you far.

Good luck using these as your lottery numbers ;)

Re: 1 kilobyte is precisely 1000 bytes?

#359

Post by whobre »

assimpleaspossi wrote: post #317
philipswood wrote: post #257

Earlier quoted context omitted.

Yes, tomato's ARE actually a fruit. But really!? I'll keep calling it in nice round powers of two, thank you very much.

Yes. Tomatoes are a fruit because the science says so. That non-scientific people call it something else does not change facts.

Context matters…

Re: 1 kilobyte is precisely 1000 bytes?

#360

Post by fallingfrog »

Yeah so I realize that at some point manufacturers of hard drives started to cheat and claim 10gb hard drives that were actually a bit less, using a 1000kb megabyte as their rationale, but that's just the marketing team engaging in false advertising. There's no reason to dignify such deception by inventing new words. They just lied. A mb is 1024 kbytes and a gb is 1024 mb. Sorry thats just how the math works out. A 16 kb address space can access 64kb or 65536 unique memory locations.
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