The Factory Floor

HDE 226868

12:34 AM

Colorful pictures make an otherwise boring scientific answer much more interesting.

Hohmannfan

12:46 AM

@HDE226868 I usually prefer to not use them, as I am that type of person just wanting the numbers, without any clutter.

But of course you get my vote

HDE 226868

@Hohmannfan I've been that way, in the past, but for answers involving simulations (which is the most recent time I've used them), it's much easier to get the point across via images. Visuals make sense to more people than equations, in most cases.

HDE 226868

1:37 AM

I complained in the past about there being fewer planet questions of late.

Tonight, there are many, and I'm in my element.

Hohmannfan

1:48 AM

@HDE226868 Is it just us two answering questions tonight?

HDE 226868

@Hohmannfan Nope. Look at the desert question, and the slavery question.

spicklesandwich

2:07 AM

I've got a couple questions on the RPG forum about my homebrew tabletop game, but they might fit better in the worldbuilding forums.
Thing is... I suck at asking specific questions. So I'm in danger of being blocked. :/
So I'd like someone to look at them to see if I can't improve them or answer them here before I put them up as questions?

http://rpg.stackexchange.com/questions/73882/how-do-i-use-advanced-communication-and-travel-in-a-game-with-multiple-settings
http://rpg.stackexchange.com/questions/73883/crossing-countermeasures-over-between-settings-either-gimped-or-op?noredirect=1#comment164444_73883

I can't figure out why I'm so bad at this! But I end up hashing it out forever instead of actually getting helpful answers, because people don't understand what I'm asking for... or something. I'm usually a much better communicator. If over-communicative.
There's GOTTA be some help for open-ended thinkers like me. >:/

Hohmannfan

@spicklesandwich They are really broad, but it may help to just ask about a specific scenario instead of the general case

spicklesandwich

But it's not specific scenarios I need help with.
It's in building /concept/. Like, 'How do I do multiplication', not 'how do I do this problem'. I can give specific examples, but the question is about the 'math', not the scenario.
I really can't think how I can be more specific than that. Is the question not clear?

I mean, I guess I can come up with a specific scenario that 'exemplifies' the issue, that maybe I'll get the question by answering... but really, if we understand the question, why can't we just answer it? Even if it's open-ended, it isn't that broad to me.

Monica Cellio

3:27 AM

@HDE226868 (or anyone else who feels inclined), I have what might be a "101 - duh!" astronomy question, so before I ask on main I'll ask you. :-) Remember that star you suggested I put in a reflection nebula to boost its light output? How, or does, the nebula modify the color of the light? Does this have a simple answer or is it interesting enough to ask on the site?

HDE 226868

3:54 AM

@MonicaCellio Scattering.

Monica Cellio

@HDE226868 I'm sorry; could you say that in a few more words? You mean some sort of spectrum-scattering thing like a prism?

HDE 226868

Particles in Earth's atmosphere scatter light, which is part of the reason for blue skies and magnificent sunsets.

Sorry, connection issues keel kicking me out of the room.

Monica Cellio

Ouch, sorry to hear. Feel free to say "later"; it's not urgent.

HDE 226868

A reflection nebula scatters light from nearby stars in the same way.

Okay, yeah, I'll have to get back to you on this.

Monica Cellio

Ok, no problem -- we'll chat when you're not having technical difficulties!

And thanks!

bilbo_pingouin

6:28 AM

22

Q: Sandbox for Proposed Questions

What is the Sandbox? This "Sandbox" is a place where Worldbuilding.SE users can get feedback on prospective questions they wish to post. This is useful because writing a clear and fully specified question on the first try can be difficult. There is a much better chance of your question being wel...

bilbo_pingouin

6:53 AM

And I haven't got into the details of your questions on RPG, but questions that are too broad usually needs to be refined to provide some information limiting the scope. And it also a good idea to provide some objective criteria on which you are going to judge the best answer. People taking time to answer your questions thrive to provide the best answer to your question. But they won't know, until they know clearly what you are expecting.

Tim B

10:46 AM

@DaaaahWhoosh you only need to check up to the square root, not up to half

Tim B

10:59 AM

@MonicaCellio If you come to London again we'll have to meet up :)

@spicklesandwich Ask about techniques to cope with the problem, not about solutions itself, and you might be ok. Make sure it's about building the world though. i.e. questions about how to handle it in the characters etc is not on topi

When moderator elections happen (we've no timetable for that yet) we'll probably get a similar number of mod slots to what we have now. Pro tem mods would need to stand for election or step down (each of us making our own decision on what to do). I know some of us are planning to stand, I don't know if all are. That shouldn't stop other people standing though :)

@spicklesandwich If you're looking for a solution to a specific case (for example a particular transition between 2 particular worlds with defined characteristics) then that would also be fine as a question although you should read the "idea generation" meta discussions for notes on stuff to avoid

bilbo_pingouin

@TimB well you guys do a great job, I don't see why we would prevent that to continue ;-)

Tim B

don't feel like you shouldn't run. Fresh blood doesn't hurt

and it's not guaranteed that we'll all stand anyway

bilbo_pingouin

11:15 AM

well James and bowlturner seemed to show some interest in it. For my part, I think I'd say something similar to bowlturner. I would not be against doing it, but I don't know if I'd actually stand for an election.

Tim B

be a bit of a boring election if we only have as many candidates as there are mod slots

bilbo_pingouin

if we come to that, I'll throw it in :)

DaaaahWhoosh

2:20 PM

@TimB Well I feel stupid now. Thanks for giving me some math to think about, now I need to go find out how to calculate the square root up front. I know how to tell if I've passed it but I can't think of how to get it initially

ooh, so I've plotted two lines, one that's x and one that's x^2, I figure if I can get the difference between the two at any point, that's how to find the square root

I think I did something like this in calculus, but it's been about four years since I did any calculus...

DaaaahWhoosh

2:36 PM

now I'm calculating the difference between perfect squares and their square roots, looks like it's a function of some sort but I am so rusty

Tim B

2:49 PM

? square root of a number is just a standard funciton, I'm not sure what you mean?

DaaaahWhoosh

@TimB I don't know it, I'm trying to find it

Tim B

if you are checking whether 10,000 is prime then square root it (100) and then check if 10,000 is a multiple of any number up to 100. (i.e in this case it fails at 2)

Hohmannfan

And after 2, you just have to check odd numbers

Tim B

yep, in fact you just need to check primes

Hohmannfan

:P

Tim B

2:52 PM

this actually came up in the interview for my current contract :D. They asked me to write something to find if a number was prime. My first pass was a loop from 2 to n/2.

They asked why n/2 and I said it's a simple optimization, can be improved....then worked out that it was root(n) and explained why

DaaaahWhoosh

@TimB But I don't know how to 'square root it' except by using a calculator

Hohmannfan

Checking divisibility on a precomputed table of prime-numbers up to $\sqrt(n)$ must be the fastest way

Or a table lookup :P

Tim B

yep, one of the interview examples we looked at wanted "all primes less than N", so I was able to use the primes found so far to speed up finding subsequent primes

@DaaaahWhoosh Not sure what you mean. You're using a programming language?

Whatever you're using will have a squareRoot function. In Java it's in Math.sqrt() for example iirc

DaaaahWhoosh

@TimB Not any more, now I'm just using pen and paper. I've switched from my computer science major to my math minor

Tim B

use your calculator :D

If you really want to do it then it's surprisingly un-simple

Methods of computing square roots

In numerical analysis, a branch of mathematics, there are several square root algorithms or methods of computing the principal square root of a nonnegative real number. For the square roots of a negative or complex number, see below. Finding is the same as solving the equation . Therefore, any general numerical root-finding algorithm can be used. Newton's method, for example, reduces in this case to the so-called Babylonian method: Generally, these methods yield approximate results. To get a higher precision for the root, a higher precision for the square is required and a larger number of steps...

DaaaahWhoosh

2:58 PM

no, see, this is how I have a good time. I've already discovered that the difference between successive perfect squares are consecutive odd numbers, whereas the difference between the differences between successive perfect squares and their square roots are consecutive even numbers

based on this, I can probably use some version of Gauss's sum-of-consecutive-numbers equation to come up with a function for square root

or, at least I can get the nearest square root of a perfect square, which is close enough for me