For the first thread, "A calculus-based course about how barrel length, rifling twist rate, powder load, wind, gopher mounds, temperature, humidity, and magnets affect trajectory (with proofs)."



It should make for an interesting discussion.

I think we have a few nerd forums.  

Maybe, but we're not talking about a nerd forum, we're talking about a geek forum.  Nerds are socially inept.  Geeks are subject experts.

Buuuuuuuuuuuuulllll-SHIT!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

I'll take my TI-speak over that god-forsaken Reverse-Polish-Notation CRAP any day of the week...thank you very much.

Better yet...MathCAD FTMFW!!!!

I agree, a science/math forum would be excellent.

So would this be a forum where we could finally find out how magnets work?  



But seriously, it doesn't sound like a  bad idea.  I deal with a bit of math at work when trying to figure out poundage of a material based on the ppm TOC (total organic carbon) and the total gallons.

+1 on the geek forum.

How about simply G33k?

Fantastic Idea...Mods/Site God, please make it so...

...

Agree.



 

I hope it doesn't turn into a "Do my homework" board, you know?

I enjoy talking about concepts and might even solve out the odd problem now and then if it interests me and I have the time but I would never visit a board full people looking for me to do their homework for them. God knows that I have enough of my own work as it is. I imagine that most here [interested in this forum] feel similarly. As such, this could never become a "do my homework" board as there would not be any willing to do it. Even if some of those threads did pop up from time to time they would most likely fail to garner any serious traffic and as such those thread authors would stop trying.



That's my theory hypothesis anyway.



 

I volunteer to mod this hypothetical forum

The line formed awhile ago and you are not in front.



 

*breaks some kneecaps* OK now I am

NERD FIGHT!



 

What? You don't want the mentally handicapped telling you that calculated distances of stars are made up?

Nixon faked the moon landing on Mars.

Philosophy/ mathematics/ sciences forum?

Yeahyyyy, boyeeee!

If we had a science & math forum, I'd have a place to talk about the artificial intelligence project I've been working on!

I talked about it in the night crew last night, but here's a taste:

hahaha  

Ooops, I never finished describing that project.

Instead of following the traditional game of life rules, each cell has a genome consisting of a language I wrote that's a subset of brainfuck. Every cell gets interpreted and depending on the result of interpretation, lives, dies, copies itself into an adjoining cell, or merges its dna with an adjoining cell. There's also a random chance of mutation - flipping a bit or two in the genome.

I'll also paste my introduction to automata from last night.


Let's talk about deterministic vs nondeterministic finite acceptors.

NFAs are a type of automata where a given state an input might map to multiple potential next states.

Let's explain deterministic finite acceptors (DFAs) first. Deterministic finite acceptors have only one transition for a given input. Here's a real world example: Let's say you have a light switch that turns the overhead light on and off. The possible inputs are "turn on" and "turn off". The possible states of the light are "on" and "off". Therefore it's easy to determine the states given an existing state and input:

* State: Light is off. Input: Turn switch on. Resultant state: Light is on
* State: Light is on. Input: Turn switch off. Resultant state: Light is off

It's called a deterministic acceptor because every input can be clearly mapped to a resultant state, or output. Turning the switch on when the light is already on is undefined, and doesn't make sense in this universe.

Let's put down some concrete definitions.

* Σ (sigma) is the input alphabet for the acceptor - i.e. what sort of inputs make sense to the machine. In the above example, Σ is "turn off" and "turn on"
* S is the set of states - what the inputs or transitions can put us into. In the above example, our states are "Light is on" and "Light is off". So S = { "Light is on", "Light is off" }
* S₀ (pronounced "S sub naught" or "S naught") is the initial state of the machine. This is something that has to be defined for a given machine. In our example, we'll define the initial state to be "Light is off"
* δ (lower case delta) is the state transition function. We define it in the realm of δ : S x Σ -> S, or in English: "Delta is defined such that given the input alphabet and any state, there is a well defined transition to another state in S". The difference between deterministic and nondeterministic finite state machines it that in nondeterministic machines, S x Σ does not have to be fully mapped. It is possible that you could be in a one state where some input wouldn't make sense, but given the formal definition of your universe, you shouldn't be in a state with invalid input for the current state.
* F is the set of final states, which is defined to be a subset of S. We can define F to be "Light is on" and "Light is off", allowing us to end in either state. Or we could impose a more rigid acceptor which only allows us to end in "Light is off" state.

So now that we have some background, let's look at the formal definition of the deterministic finite acceptor for the light switch example.

* Σ = { "Turn switch on", "Turn switch off" }
* S = { "Light is on", "Light is off"
* S₀ = "Light is on"
*  δ : S x Σ -> S
* F = "Light is on"

In this example, we've defined the initial state to be "Light is on" and the final state is "Light is on" - for some reason we can't leave the room if it's off!

Now it's time to introduce the DFA diagram for this example.



The circles represent states, S₀ and S₁. These map into our S definition from above, i.e. S₀ = "Light is on" and S₁ = "Light is off". The bold circle around one of the states means that state is a member of F, i.e. that's a valid final state.

The arrow from the left means that S₀ is our initial state. Recall from our definition of S above that this means that we start out with the light turned on.

The arrows between the state circles show the valid transitions. If we're in S₀ we can transition to S₁ by following the transition "Turn switch off". Likewise, if we are in state S₁ we can transition to S₀ by following the transition "Turn switch on."

Cool, so now that we have a real-world definition of a DFA that we can relate to, let's look at how something like this is generally discussed in automata theory.

*  Σ = { 0, 1 }
* S = { A, B }
* S₀ = A
*  δ : S x Σ -> S
F = { A }

Transition diagram:


State diagram:

Did you just use a lot of jargon to explain what a truth table is?

I like you.  

Well,

truth tables are part of it (although we call them transition diagrams). But there's a lot more to finite acceptors than truth tables. I'll probably do a small dissertation on nondeterministic finite acceptors tonight in the night crew then paste it over here when I'm done.

I can haz science/math forum?

Holy shit, after looking over DlzBenz's recent thread, I remembered this one and tried to find it.  Like a tard, I couldn't.

What about tickling the penguin?