It's the same in the the standard c library, so Java is being consistent with a real programming language…
Java
Submitted 10 months ago by alphacyberranger@lemmy.world to programmer_humor@programming.dev
https://lemmy.world/pictrs/image/94f08bca-118d-48e1-9992-b48892db83b4.png
Comments
jayrhacker@kbin.social 10 months ago
idunnololz@lemmy.world 10 months ago
Implying java isn’t a real programming language. Smh my head.
Glome@feddit.nl 10 months ago
Java has many abstractions that can be beneficial in certain circumstances. However, it forces a design principle that may not work best in every situation.
I.e. inheritance can be both unnatural for the programmer to think in, and is not representative of how data is stored and manipulated on a computer.
jayrhacker@kbin.social 10 months ago
Java is, of course, Turing Complete™️ but when you have to hide all the guns and knives in jdk.internal.misc.Unsafe something is clearly wrong.
korstmos@kbin.social 10 months ago
Doubles have a much higher max value than ints, so if the method were to convert all doubles to ints they would not work for double values above 2^31-1.
(It would work, but any value over 2^31-1 passed to such a function would get clamped to 2^31-1)
karlthemailman@sh.itjust.works 10 months ago
So why not return a long or whatever the 64 bit int equivalent is?
whats_a_refoogee@sh.itjust.works 10 months ago
To avoid a type conversion that might not be expected. Integer math in Java differs from floating point math.
Math.floor(10.6) / Math.floor(4.6) = 2.5 (double)
If floor returned a long, then
Math.floor(10.6) / Math.floor(4.6) = 2 (long)
If your entire code section is working with doubles, you might not like finding Math.floor() unexpectedly creating a condition for integer division and messing up your calculation. (Have fun debugging this if you’re not actively aware of this behavior).
korstmos@kbin.social 10 months ago
Because even a long (64-bit int) is too small :)
A long can hold 2^64-1 = 1.84E19
A double can hold 1.79E308Double does some black magic with an exponent, and can hold absolutely massive numbers!
Double also has some situations that it defines as "infinity", a concept that does not exist in long as far as I know (?)
parlaptie@feddit.de 10 months ago
But there’s really no point in flooring a double outside of the range where integers can be represented accurately, is there.
affiliate@lemmy.world 10 months ago
what about using two ints
korstmos@kbin.social 10 months ago
A BigDecimal?
MarekKnapek@programming.dev 10 months ago
Makes sense, how would you represent
floor(1e42
) orceil(1e120)
as integer? It would not fit into 32bit (unsigned) or 31bit (signed) integer. Not even into 64bit integer.maniacal_gaff@lemmy.world 10 months ago
It would be kinda dumb to force everyone to keep casting back to a double, no? If the output were positive, should it have returned an unsigned integer as well?
larvyde@sh.itjust.works 10 months ago
int
coerces todouble
automatically, without explicit castingsnake_baitman@lemmy.sdf.org 10 months ago
The CPU has to do real work to convert between float and int types. Returning an int type would just be giving the CPU extra work to do for no reason
baseless_discourse@mander.xyz 10 months ago
I think one of the main reason to use floor/ceilling is to predictably cast a double into int. This type signature kind of defeats this important purpose.
I don’t know this historical context of java, but possibly at that time, people see type more of a burden than a way to garentee correctness? (which is kind of still the case for many programmers, unfortunately.
BorgDrone@lemmy.one 10 months ago
You wouldn’t need floor/ceil for that. Casting a double to an int is already predictable as the java language spec explicitly says how to do it, so any JVM will do this the exact same way.
The floor/ceil functions are simply primitive math operations and they are meant to be used when doing floating point math.
rev@ihax0r.com 10 months ago
python is like this also. I don’t remember a language that returned ints
shotgun_crab@lemmy.world 10 months ago
Python 2 returns a float, Python 3 returns an int iirc.
CaptainHowdy@lemm.ee 10 months ago
My God this is the most relevant meme I’ve ever seen
Acetamide@lemmy.world 10 months ago
AFAIK most typed languages have this behaviour.
Lmaydev@programming.dev 10 months ago
Because ints are way smaller. Over a certain value it would always fail.
larvyde@sh.itjust.works 10 months ago
Yea but at those values floating points can’t represent fractions anyway
Aelorius@jlai.lu 10 months ago
Logic, in math, if you have a real and you round it, it’s always a real not an integer. If we follow your mind with abs(-1) of an integer it should return a unsigned and that makes no sense.
kogasa@programming.dev 10 months ago
in math, if you have a real and you round it, it’s always a real not an integer.
No, that’s made up. Outside of very specific niche contexts the concept of a number having a single well-defined type isn’t relevant in math like it is in programming. The number 1 is almost always considered both an integer and a real number.
If we follow your mind with abs(-1) of an integer it should return a unsigned and that makes no sense.
How does that not make sense? abs is always a nonnegative integer value, why couldn’t it be an unsigned int?
Aelorius@jlai.lu 10 months ago
I’m ok with that, but what I mean is that it makes no sense to change the type of the provided variable if in mathematics the type can be the same.
jimbo@lemmy.world 10 months ago
What? In math, integers can be negative.
bappity@lemmy.world 10 months ago
the programming language Java meaning coffee is perfect because, like coffee, it tastes like shit but gets the job done
MrGeekman@lemmy.world 10 months ago
I think you need to try some lighter-roasted, higher-quality beans which were roasted fairly recently and only grind them a day or so before you use them. There are also different brewing methods and coffee/water ratios that you can try.
mestari@lemmy.world 10 months ago
I love and consume lots of coffee but I sincerely believe it only tastes good because I associate the taste with the boost it gives. Exactly like cigarettes taste tolerable, good even, when you smoke them regularly.
cia@lemm.ee 10 months ago
It is shit, Austin
Fantasmita@lib.lgbt 10 months ago
It’s like Java not having unsigned integers…
dylanTheDeveloper@lemmy.world 10 months ago
I like big numbers and I cannot tell a lie
MrGeekman@lemmy.world 10 months ago
Try Math.round. It’s been like ten years since I used Java, but I’m pretty sure it’s in there.
jayrhacker@kbin.social 10 months ago
It's the same in the the standard c library, so Java is being consistent with a real programming language…
RoyaltyInTraining@lemmy.world 10 months ago
Makes sense, cause double can represent way bigger numbers than integers.
lysdexic@programming.dev 10 months ago
Also, double can and does in fact represent integers exactly.
Killing_Spark@feddit.de 10 months ago
Only to 2^54. The amount of integers representable by a long is more. But it can and does represent every int value correctly
fsxylo@sh.itjust.works 10 months ago
Also because if you are dealing with a double, then you’re probably dealing with multiple, or doing math that may produce a double. So returning a double just saves some effort.
pomodoro_longbreak@sh.itjust.works 10 months ago
Yeah it makes sense to me. You can always cast it if you want an int that bad. Hell just wrap the whole function with your own if it means that much to you
(Not you, but like a hypothetical person)
disencentivized@programming.dev 10 months ago
Why not just return a long?
RoyaltyInTraining@lemmy.world 10 months ago
A double can represent numbers up to ± 1.79769313486231570x10^308, or roughly 18 with 307 zeroes behind it. You can’t fit that into a long, or even 128 bits. Even though rounding huge doubles is pointless, since only the first dozen digits or so are saved, using any kind of Integer would lead to inconsistencies, and thus potentially bugs.
Beanie@programming.dev 10 months ago
doubles can hold numbers way larger than even 64-bit ints
thegamer@burggit.moe 10 months ago
A double could also be NaN and any operations with NaN should return NaN afaik
karlthemailman@sh.itjust.works 10 months ago
How does that work? Is it just because double uses more bits? I’d imagine for the same number of bits, you can store more ints than doubles (assuming you want the ints to be exact values).
nile@sopuli.xyz 10 months ago
No, it has an exponent component: …wikipedia.org/…/Double-precision_floating-point_…