Doubt

[subtle oriole]

Math.sqrt(-1) returns NaN. What type of error should this be? At the first glance, it looks like a logical error, since root of a negative number(negative 1, here) is i(mathematical constant). I had this question in a test as well, however the right answer was marked as "runtime", and google says the same. I'm not saying google is 100% authentic but I didn't find any answers saying logical error

[burnt moth]

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TIP: Narrow down your issue to simple and precise questions to maximize the chance that others will reply in here.

This is not a JavaScript server. [Java](https://en.wikipedia.org/wiki/Java_(programming_language) and JavaScript are completely different languages. See: How is JavaScript different from Java?

[subtle oriole]

yeah, im asking about java, not javascript

I don't see myself mentioning that my query concerns javascript and not java, and since it is a java server the latter should be more obvious, no offense

[lusty palm]

NaN is js

[subtle oriole]

it is java as well

unless you say bluej isn't authentic

import java.util.*;
class Example {
    public static void main() {
        print p=new print();
        System.out.println(Math.sqrt(36-45));
    }
}```

[lusty palm]

/run ```java
System.out.println(Math.sqrt(36-45));

[vagrant jacinth]

Here is your java(15.0.2) output @lusty palm

NaN

[subtle oriole]

^

[lusty palm]

my bad, I assumed java would throw exception

[subtle oriole]

its alright lol it happens.. the fact that it does not throw an exception is why I thought it would be a logical error

but it turns out to be a runtime error which doesn't really make sense to me

[queen adder]

NaN is IEEE 754

[queen adder]

if by "runtime error" it means a RuntimeException, it shouldn't be that

[subtle oriole]

I was wondering the same, but again I tried searching it up and all of it said runtime error

[queen adder]

i'd say it's an arithmatic/mathematical error in the same vein as 1.0/0

it's an issue that occurs at runtime, but it's not an Exception

that's the main issue here tbh, "error" is vague with java

[subtle oriole]

right

also any idea why 0.0/0, or any double by 0 returns infinity/NaN but when you make it an integer by 0 it returns an arithmetic error?

35.0/0 would return infinity but 35/0 would be an arithmetic exception

[queen adder]

"error" could mean 1 of 3 things

• any issue at all
• a compiler error
• a runtime error, perhaps matching to a class

a language like js might be less vague here, as its "issue" class is Error
but java's Error is much more niche, and general issues use Exception instead

[queen adder]

1.0/0 is doing floating-point arithmetic in accordance to IEEE 754 as i mentioned before, so it can represent that as Infinity, but 1/0 is integer arithmetic, where it is undefined

[subtle oriole]

so, the Math.sqrt of a negative number is a logical error, right?

[subtle oriole]

oh, alright

thank you

[burnt moth]

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[queen adder]

floating-points don't have a true representation of mathematical 0, every value is an approximation, there's limited precision
so if you had a really really small number, that would get turned into 0
a random number divided by a really small number is a really big number, which is represented by Infinity

this is also why -0 exists, very small number that is negative, 1.0/-0.0 is -Infinity

[subtle oriole]

yeah that makes sense

[subtle oriole]

oh

but isn't -0.0 or 0 the same

[queen adder]

if you have 0.0/0.0, you can't know which one is actually smaller, so that turns into NaN

[queen adder]

in math yes, for floating-points no

[subtle oriole]

oh alright

[subtle oriole]

oh

[queen adder]

https://www.youtube.com/watch?v=dQhj5RGtag0
this may be of interest

[subtle oriole]

I did try compiling 1.0/-0, however it returned Infinity

[subtle oriole]

thank you, ill check it out in a bit

[queen adder]

hard to say. "logical error" isn't well-defined, it seems quite subjective imo

[subtle oriole]

/run
System.out.println(1.0/-0);

[vagrant jacinth]

@subtle oriole

Error

Invalid command format (missing codeblock?)

[subtle oriole]

/run

System.out.println(1.0/-0)```

[vagrant jacinth]

@subtle oriole

Error

Unsupported language: None
Request a new language

[subtle oriole]

/run

System.out.println(1.0/-0)```

[vagrant jacinth]

@subtle oriole I only received java(15.0.2) error output

file0.code.java:2: error: ';' expected
System.out.println(1.0/-0)
                          ^
1 error
error: compilation failed

[subtle oriole]

/run

System.out.println(1.0/-0);```

[vagrant jacinth]

Here is your java(15.0.2) output @subtle oriole

Infinity

[subtle oriole]

sorry for the mess-

[queen adder]

-0 is the unary operator - applied to an integer 0, which is exact and yields 0
then 0 is coerced to the double 0.0 for the operation

[subtle oriole]

oh alright fair -0.0 returns -Infinity

[queen adder]

/run

System.out.println(1.0/-0.0);

[vagrant jacinth]

Here is your java(15.0.2) output @queen adder

-Infinity

[subtle oriole]

so, no error?

[queen adder]

yeah

[queen adder]

that loops back to this really

[subtle oriole]

oh alright

so its no error, that is fair

[queen adder]

if by "error" you mean "issue", then sure, it could be considered a logical error
but if by "error" you mean Exception, then no, there's no error here, just an issue
strictly adhering to terms, the latter would be more correct and useful, but the former tends to be used more loosely

so it's really hard to say here

[subtle oriole]

makes sense to me now, thank you so much for the time

[burnt moth]

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[subtle oriole]

do I close this?

[queen adder]

if you're satisfied with my answer, sure i guess
i probably wouldn't be lol

[subtle oriole]

I didn't want to go into too much depth, I just had this in an exam last time and while revising I saw this again, so I was pretty confused what it should have been

[queen adder]

if im being honest, sounds like a badly-written question, it's not specific enough

probably relies on how the teacher/curriculum specifically taught it rather than more exact terms

[subtle oriole]

my bad on that

[queen adder]

nah that's definitely not your bad lol

[subtle oriole]

we have pretty basic java stuff, I was stuck on this and that's all I was wondering, I just needed a clarification over the fact that whether it was a runtime error or not (since it made no sense to be so, yet all sources cited to the same answer)

and I really appreciate your help and patience

[queen adder]

what sources did you find that stated it to be a "runtime error"? im curious on how that came up

[subtle oriole]

by sources, I basically mean all answers I found on google, which im not saying is authentic again, but that's what came up

stuff like this is misleading, I could say

[queen adder]

"Run time error"

[lusty palm]

yeah I would expect an error reading this

[queen adder]

the spacing there is... wow

yeah i would not trust this source

[subtle oriole]

yeah doesn't make sense at all

[subtle oriole]

right, pretty misleading 😭

this doesn't make sense either

I did find 1 answer which said logical, but again majority of the answers cited towards runtime which led to me getting a bit confused 😅

chatgpt said runtime as well, for some reason

[queen adder]

using these definitions, it's at least self-consistent at least

"runtime error" still isn't correct imo, but it's the least wrong option from these

[queen adder]

if this was an option it'd probably be this instead

[subtle oriole]

oh

[queen adder]

"logical error" is more commonly used for stuff like ifs/whiles/fors being set up wrong for example

so yeah i can see why that isn't the "correct" one for this

[subtle oriole]

oh alright

thank you again

[burnt moth]

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If you are not, please ignore this message.
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[quiet cloak]

true

[quiet cloak]

yeah

[quiet cloak]

that's true too

[quiet cloak]

cool

[quiet cloak]

ikr lol

i and @subtle oriole and technically the students of our batch were confused af 💀

[queen adder]

could you like not spam ping me thanks

[quiet cloak]

whoops sorry i should have disabled mentioned replies sry

[subtle oriole]

yes please, im sorry on his behalf

[quiet cloak]

uh