Search found 177 matches

by Nyktos
Fri Jul 21, 2017 4:12 pm UTC
Forum: Religious Wars
Topic: Graph theory terminology
Replies: 16
Views: 3639

Re: Graph theory terminology

Does anyone really say "line"? I've heard "link", but not that. And "arc" is usually only used in the directed case, in which case you could also throw in "arrow" as an option. I was never taught graph theory formally and neither were my peers, soo... anythin...
by Nyktos
Mon Jul 17, 2017 3:18 pm UTC
Forum: Forum Games
Topic: What is in Your Clipboard?
Replies: 3386
Views: 467688

Re: What is in Your Clipboard?

Lindström
by Nyktos
Thu Jul 13, 2017 6:40 pm UTC
Forum: Religious Wars
Topic: Graph theory terminology
Replies: 16
Views: 3639

Re: Graph theory terminology

Does anyone really say "line"? I've heard "link", but not that. And "arc" is usually only used in the directed case, in which case you could also throw in "arrow" as an option. The different terms for vertices are a legitimate source of disagreement. In my exp...
by Nyktos
Sun Jun 25, 2017 3:41 am UTC
Forum: Religious Wars
Topic: Spaces in paths & filenames
Replies: 45
Views: 4613

Re: Spaces in paths & filenames

I often do not trust programs to correctly interpret paths/names with spaces, so I try to put all files that are to be used by a program in a spaceless path. Documents (spreadsheets and stuff) can go where ever. What are you doing with those spreadsheets that doesn't involve them being used by any ...
by Nyktos
Fri Jun 23, 2017 9:39 pm UTC
Forum: Coding
Topic: Basic Question Involving Functions (Python)
Replies: 18
Views: 4146

Re: Basic Question Involving Functions (Python)

can handle integers and strings and even arrays. if they are integers, it will add them as expected and return the result. if strings, it will concatenate them and return. if arrays, it will add the elements of the the arrays ([1,2,3]+[4,5,6] = [5,7,9]) This is not correct. While what you wrote arg...
by Nyktos
Thu Jun 22, 2017 3:48 pm UTC
Forum: Coding
Topic: Coding: Fleeting Thoughts
Replies: 9764
Views: 1573404

Re: Coding: Fleeting Thoughts

I assume there's a good chance you're stuck on Python 2, but in modern versions you'd see both tracebacks by default.
by Nyktos
Thu May 25, 2017 12:45 am UTC
Forum: Mathematics
Topic: Confused: how does ZFC allow surreal numbers?
Replies: 4
Views: 1693

Re: Confused: how does ZFC allow surreal numbers?

It doesn't work in ZFC, in the same way that defining cardinals as isomorphism classes of sets doesn't work in ZFC. There exist set-theoretic tricks for making sense of this idea, which also work here if this MathOverflow answer is to be believed. If I recall correctly, Conway himself considers the ...
by Nyktos
Fri Oct 07, 2016 3:43 pm UTC
Forum: Religious Wars
Topic: Plural of "Octopus"
Replies: 89
Views: 45914

Re: Plural of "Octopus"

1 Or "Lego" or "LEGO", but never /legos/i. (Sand grains, lego bricks. Pile of sand, sack of lego.) :shock: Careful now. I've been down this road before... It's only the Brits that have this one right. I'm Canadian and was weirded out when I started encountering the assertion tha...
by Nyktos
Thu Oct 06, 2016 9:02 pm UTC
Forum: Mathematics
Topic: 1 is Not Prime
Replies: 17
Views: 3955

Re: 1 is Not Prime

Historically number theory was often referred to as "arithmetic", and occasionally it still is. (This is basically analogous to the way mathematicians use "algebra" and "geometry" to describe branches of mathematics that in their modern incarnations don't have much obvi...
by Nyktos
Mon Oct 03, 2016 5:21 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 1741: "Work"
Replies: 53
Views: 9060

Re: 1741: "Work"

Do cups with fewer person-hours of design and debate tip more or less frequently than those designed in 'haste'? As far as the switch being on the cord, I'd hope that particular lamp is plugged in to a switched outlet. I, personally, wouldn't want a switched cord on a desk lamp where the switch was...
by Nyktos
Wed May 18, 2016 9:56 pm UTC
Forum: Religious Wars
Topic: Pronouncing RFID
Replies: 3
Views: 3748

Re: Pronouncing RFID

In my mind I hear "are-fid" when I read this word, but I suspect I'd just spell it out if I ever had cause to say it out loud.
by Nyktos
Thu Apr 14, 2016 5:00 pm UTC
Forum: Religious Wars
Topic: Is 1 prime?
Replies: 30
Views: 13388

Re: Is 1 prime?

heuristically_alone wrote:Just want to point out that 1 wouldn't be alone. 1 and -1 would be in that subcategory. Nobody wants to be alone.
If -1 is prime, surely 1 is composite. It's -1 squared!
by Nyktos
Thu Apr 14, 2016 4:16 am UTC
Forum: Religious Wars
Topic: Is 1 prime?
Replies: 30
Views: 13388

Re: Is 1 prime?

You can't discriminate a number just because it doesn't follow all of the properties the other primes might have. It's practically racist. A platypus is a mammal even though it doesn't have most properties most other mammals have. It is considered a mammal because it fits the basic definition. Biol...
by Nyktos
Mon Apr 11, 2016 7:22 pm UTC
Forum: Religious Wars
Topic: Is 1 prime?
Replies: 30
Views: 13388

Re: Is 1 prime?

Neither 1 nor -1 has a prime factor, because they are both units. You can't solve a problem by stating a tautology, Nyktos. Everyone knows 1 or -1 is also called a unit. But all prime numbers have 1 or -1 as a factor. As do all numbers (except possibly zero) Yes, all numbers are divisible by 1 and ...
by Nyktos
Mon Apr 11, 2016 1:19 am UTC
Forum: Religious Wars
Topic: Is 1 prime?
Replies: 30
Views: 13388

Re: Is 1 prime?

But you still need some restriction there, or you have (-2)*(-3) = 2*3, and 6 no longer has a unique prime factorisation. Meanwhile, -1 has no prime factors at all. Neither 1 nor -1 has a prime factor, because they are both units. 6 already doesn't have a unique factorization, as it is both 2*3 and...
by Nyktos
Sun Apr 10, 2016 6:08 pm UTC
Forum: Religious Wars
Topic: Is 1 prime?
Replies: 30
Views: 13388

Re: Is 1 prime?

phlip wrote:which... seems to be claiming that negative integers can be prime, which... seems even worse than 1 being prime.
You need to allow negative primes in order to appropriately generalize the concept of prime to rings which don't have a notion of "positive" and "negative".
by Nyktos
Fri Jan 08, 2016 2:58 am UTC
Forum: Religious Wars
Topic: Is 1 prime?
Replies: 30
Views: 13388

Re: Is 1 prime?

1 is not prime because it is not useful to define it to be prime. If 1 is prime, all the theorems about prime numbers don't start applying to 1, nor do they stop existing all together: they just become theorems about non-unit primes instead. Writing "non-unit prime" all the time is a waste...
by Nyktos
Sun Dec 13, 2015 7:52 pm UTC
Forum: Coding
Topic: Organising Wrestling DVDs via MySQL Database/PHP
Replies: 39
Views: 8414

Re: Organising Wrestling DVDs via MySQL Database/PHP

Xanthir wrote:Yeah, you gotta learn how to properly escape things for the context. For PHP, when you insert "outside" data into a SQL query use mysql_real_escape_string() on the data;
Does PHP not support parametrized queries?
by Nyktos
Thu Dec 03, 2015 3:23 am UTC
Forum: Mathematics
Topic: hotel infinity and countably infinite
Replies: 31
Views: 3599

Re: hotel infinity and countably infinite

I find the power set argument cleaner, especially since you can formulate it in a way that resembles Russell's paradox. If f is a bijection (actually we only need to assume it's a surjection) from X to its power set, the set Y = { x ∈ X : x ∉ f ( x )} must be the image of some point y , and then bot...
by Nyktos
Tue Dec 01, 2015 3:57 am UTC
Forum: Mathematics
Topic: hotel infinity and countably infinite
Replies: 31
Views: 3599

Re: hotel infinity and countably infinite

I'm curious, tho - why convert to binary? There doesn't seem to be any particular reason to do so, as the construction works just as well in decimal - (123, 5) maps to 102035, and similarly an arbitrary number like 12345 maps to (135, 24). Yeah there's no real reason to use binary actually. I had s...
by Nyktos
Tue Dec 01, 2015 2:03 am UTC
Forum: Mathematics
Topic: hotel infinity and countably infinite
Replies: 31
Views: 3599

Re: hotel infinity and countably infinite

That's not a bijection, as many of the integers aren't mapped to - in particular, anything with a 0 for its second digit. I don't know what you mean by this. 10 has zero as its second digit, and it's the image of (1, 0). Or did you mean second in the other direction? 101, for instance, is the image...
by Nyktos
Mon Nov 30, 2015 11:02 pm UTC
Forum: Mathematics
Topic: hotel infinity and countably infinite
Replies: 31
Views: 3599

Re: hotel infinity and countably infinite

N 2 is indeed > N, but its still "countable" because N 2 can be contained in a finite number of dimensions of size N (specifically 2). That's not what countable means. Countable means you can literally count it - you can rearrange the set so that there is a natural number corresponding to...
by Nyktos
Mon Nov 30, 2015 3:13 am UTC
Forum: Mathematics
Topic: hotel infinity and countably infinite
Replies: 31
Views: 3599

Re: hotel infinity and countably infinite

Cradarc wrote:Any integer must contain a finite number of digits
What about 0.999...?
by Nyktos
Mon Nov 30, 2015 1:17 am UTC
Forum: Mathematics
Topic: hotel infinity and countably infinite
Replies: 31
Views: 3599

Re: hotel infinity and countably infinite

prove that not every irrational number will be on bus 2. i can't accept the standard proof here, because the bus is infinitely long, and contains an infinite number of irrationals all "randomly" generated, so if it differs by 1 decimal place, somewhere else may contain the corrected versi...
by Nyktos
Mon Oct 05, 2015 11:24 pm UTC
Forum: Mathematics
Topic: Axioms and multiplication?
Replies: 18
Views: 2838

Re: Axioms and multiplication?

I'm gonna say it again: all the completeness axioms are the same for an ordered field. The page you linked claims otherwise. For an ordered field, Cauchy completeness is weaker than the other forms of completeness on this page. But Cauchy completeness and the Archimedean property taken together are...
by Nyktos
Thu Aug 27, 2015 3:26 am UTC
Forum: Science
Topic: How does "The Dress" illusion work on a computer screen?
Replies: 12
Views: 2771

Re: How does "The Dress" illusion work on a computer screen?

That metaphor doesn't work. Your photo would obviously appear to everyone to be red. Yes, we could understand that your dress is actually white and merely appears red because red light is being shined on it. But people wouldn't perceive it to be different than the actual RGB values of the image fil...
by Nyktos
Tue Aug 25, 2015 12:25 am UTC
Forum: Science
Topic: How does "The Dress" illusion work on a computer screen?
Replies: 12
Views: 2771

Re: How does "The Dress" illusion work on a computer screen?

Right. I could take a picture of a white dress under, say, red light. Undoubtedly if you examined the RGB values of the pixels making up the image of the dress, they would be shades of red or pink. But people would likely have no trouble telling that the dress is actually white, because the human br...
by Nyktos
Sat Aug 22, 2015 2:41 am UTC
Forum: Logic Puzzles
Topic: Who is What?
Replies: 21
Views: 2920

Re: Who is What?

I suspect the puzzle is trying to be a different puzzle entirely where we assume that all references to "The Engineer" and "The Programmer" can refer to any engineer/programmer rather than a specific one and that one of the brothers is both so what appears to be a contradiction ...
by Nyktos
Tue Aug 18, 2015 11:07 pm UTC
Forum: Coding
Topic: Coding: Fleeting Thoughts
Replies: 9764
Views: 1573404

Re: Coding: Fleeting Thoughts

Alternatively, you could just create a new class that inherits from the module class -- with x as a @property -- and find a way to create a module with *that* class instead of the standard module class. You can do this with import hooks, though of course for that to work you need to arrange to have...
by Nyktos
Sun Aug 16, 2015 11:33 pm UTC
Forum: Coding
Topic: Coding: Fleeting Thoughts
Replies: 9764
Views: 1573404

Re: Coding: Fleeting Thoughts

I would consider that ugly. Sometimes a function returning different types based on the input is reasonable but that usually takes the shape "output type is the same as input type" or something along those lines. In your case I think it would be better to just give class X a different meth...
by Nyktos
Mon Jun 08, 2015 6:47 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 1535: "Words for Pets"
Replies: 40
Views: 9328

Re: 1535: "Words for Pets"

I think I got stuck in the "second year" phase. For the last few years of my friend Catherine's life I pretty much always just called him "cat".
by Nyktos
Tue Apr 28, 2015 5:59 am UTC
Forum: Coding
Topic: Coding: Fleeting Thoughts
Replies: 9764
Views: 1573404

Re: Coding: Fleeting Thoughts

Nyktos, in C++ variables are names for things. The thing they are a name for never changes (so long as it exists) in its fundamental nature. That thing can be a *pointer* to another thing if you want. A reference is an alternative name for a thing, and similarly what it refers to never changes (so ...
by Nyktos
Sat Apr 25, 2015 2:44 am UTC
Forum: Coding
Topic: Coding: Fleeting Thoughts
Replies: 9764
Views: 1573404

Re: Coding: Fleeting Thoughts

...which makes me think you could use a similar technique to 'jury-rig' constraints on variables (by assigning them to objects that do insidious shit when you try to delete them). Dunno if that would work, though (and it's definitely very unpythonic!). That won't work if you end up with other refer...
by Nyktos
Sat Feb 28, 2015 7:23 pm UTC
Forum: Religious Wars
Topic: Braces vs indent vs "end ..." syntax preference
Replies: 49
Views: 15836

Re: Braces vs indent vs "end ..." syntax preference

ucim wrote:But in the meanwhile more code is visible in the window, which is a good thing.
I agree. It's annoying when less code fits on screen because a fifth of your lines are just "end" or "}".
by Nyktos
Wed Feb 25, 2015 3:44 pm UTC
Forum: Religious Wars
Topic: Braces vs indent vs "end ..." syntax preference
Replies: 49
Views: 15836

Re: Braces vs indent vs "end ..." syntax preference

ucim wrote:if (condition)
..do this
if (another condition)
..do that
if (a third condition && a fourth condition)
..do something else
Python has absolutely no problem with "if condition: do_a_thing()" on one line.
by Nyktos
Tue Feb 17, 2015 6:39 pm UTC
Forum: Language/Linguistics
Topic: Mobile?
Replies: 9
Views: 3567

Re: Mobile?

I always say "mo-bile", including for the baby thing, but I hear "moble" reasonably often around here (Toronto) as well, mostly for phone-related things.
by Nyktos
Mon Feb 16, 2015 4:12 am UTC
Forum: Coding
Topic: Coding: Fleeting Thoughts
Replies: 9764
Views: 1573404

Re: Coding: Fleeting Thoughts

I get 9223372036854775807 (2^63 - 1) on both Python 2 and 3.

Some digging finds that sys.maxsize is PY_SSIZE_T_MAX which is platform-dependant and definitely not always the same as INT_MAX.
by Nyktos
Wed Jan 21, 2015 2:13 am UTC
Forum: Coding
Topic: Coding: Fleeting Thoughts
Replies: 9764
Views: 1573404

Re: Coding: Fleeting Thoughts

I'm not very well versed in C++ so I'll being deferring to your knowledge and expertise on most of that. As far as optional<optional<X>> goes, in all the literature and examples I've seen it could just be flattened to optional<X>. That outer wrapping isn't really serving much purpose. In Rust, iter...
by Nyktos
Wed Jan 14, 2015 5:29 pm UTC
Forum: Religious Wars
Topic: Is 0 a natural number?
Replies: 35
Views: 13768

Re: Is 0 a natural number?

Way back when, I learned that "whole" numbers are {1, 2, ...} and natural numbers are {0, 1, ...}. Or maybe it was the other way around. Maybe I should say "I was taught" instead. :-) I'm certain that in high school I was taught that "whole numbers" include zero and na...
by Nyktos
Wed Jan 14, 2015 3:26 am UTC
Forum: Religious Wars
Topic: Is 0 a natural number?
Replies: 35
Views: 13768

Re: Is 0 a natural number?

The natural numbers are simply those that occur as the sizes of finite sets (including the empty set). Any other definition is unnatural.

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