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    C/++/# [C++] Never have more than 1 return statement?

    I agree with most of the posts in this thread. IMO, it's completely pointless to force a single return when many would simplify the code. But I have a professor that enforces the single return rule on all of his assignments. I've mentioned to him that I think the rule is absurd (it's a small...
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    Free Market Currency 'Bitcoin'

    What happened to self ownership? Is it not vain to assume that your view that investment in something is insane must be the correct view? By what objective reasoning could you justify subjecting everyone of the opposing view to some arbitrary standard to act on their view?
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    Found a cool Non-autonomous Coupled System of ODEs

    Also, I've reduced it to a system of very complex 2nd order noncoupled ODEs, but that doesn't seem to help in solving it. Mathematica can't solve it either. I'm almost convinced it isn't solvable. So it seems the only way to explore it is with numerical methods.
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    Found a cool Non-autonomous Coupled System of ODEs

    By a fortuitous mistake in copy/pasting, I happened across this system. It exhibits very chaotic behavior for some initial values and spiral-like shapes for others. (About a 70%/30% split, respectively.) x'=cosy+sint y'=sinx+cost Here's an album of it plotted from t=0 to 1000. The titles of...
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    Coauthoring papers as an undergrad (as a programmer slave)

    To what extent? I mean, I can say they found some cool way of saying that the max clique of graphs with a certain type of generator is equal to the max clique of a specific subgraph plus some constant. (I know about the generator and how to construct the subgraph, but I don't want to do into...
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    Coauthoring papers as an undergrad (as a programmer slave)

    I've been given the opportunity to write programs for two different professors working on separate papers (one math, one physics), and when published they say they will list me as a coauthor. With the first, I sorta resisted a little, because I don't see the amount of work I did as really...
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    Free Market Currency 'Bitcoin'

    You should look into peercoin. It's one of many cryptos that have a hybrid proof of work and proof of stake minting scheme. The idea is that mining will generate initial amounts and when it losses profitability, then users will generate coins using proof of stake. Proof of stake works like...
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    Free Market Currency 'Bitcoin'

    Overstock.com plans to begin accepting BTC in 2014. http://www.forbes.com/sites/amitchowdhry/2013/12/21/overstock-com-is-going-to-accept-bitcoin-in-2014/ Here's to hoping Amazon will follow. That'll cause a spike like never before.
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    Free Market Currency 'Bitcoin'

    phinds, I used dollar signs didn't I? Or am I missing some meaning in the way you worded that?
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    Free Market Currency 'Bitcoin'

    That is where most of the trading comes from. I mean, look at the volume (http://bitcoinwisdom.com/markets/btce/btcusd). Surely drug dealers and buyers aren't buying and selling BTC at around 5 transactions per minute. And at the exchange I frequent, there's consistently over 5,000 people on...
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    Free Market Currency 'Bitcoin'

    On Silk Road, transactions where hedged. As in, if you sold your drugs for $50 worth of BTC, you get $50 worth of BTC at the end of the transaction. (There was significant delay between the sell and the end of the transaction because SR had an escrow system.) I don't know how all the smaller...
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    Global max of a multivar func when restriced to a given plane.

    Oh! That's actually a sorta natural extension to the 3d stuff I learned in calc 3. Thanks!
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    Global max of a multivar func when restriced to a given plane.

    On this year's Virginia Tech test there was a problem to prove: \frac{x}{1+x^2}+\frac{y}{1+y^2}+\frac{z}{1+z^2}\leq \frac{3\sqrt{3}}{2} when x+y+z=xyz So my approach was to consider the function, f, where f(x, y, z)=\frac{x}{1+x^2}+\frac{y}{1+y^2}+\frac{z}{1+z^2} then restrict f to the...
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    Extensible phone design! - Phonebloks

    It may be impossible. I was under the impression that phones are designed in such weird ways to try to pack as much stuff into the given volume as possible. But, that could just as possibly be an excuse for not having replaceable/upgradable parts and thus forcing new purchases. Idk. If you like...
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    Metric for rating funtion accuracy from R^m to R.

    I went with the abs value one because, by nature of the fact they're all random, there are going to be a lot of bad solutions. So I thought a metric which doesn't underestimate their badness would be better. Thanks.
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    Metric for rating funtion accuracy from R^m to R.

    I'm writing program in which I generate pseudo random expressions with the hope of finding one that closely approximates the given data set. The functions map from R^m (an m-tuple of reals) to a real. What I need is a way to rate the functions by their accuracy. Are there any known methods for...
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    Numerical Approximation of a 4D System of ODE's

    What are some implicit methods that you would recommend? With generality being the most favored quality. I'm okay with the algorithm being harder and slower, it's all going to be precomputed anyway. When I said I didn't want to solve implicit equations, I was only really talking about...
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    Numerical Approximation of a 4D System of ODE's

    What is the most general method of approximating arbitrary systems of ODEs of 4 variables(x,y,z,t) that fit these conditions? The conditions that are assumed true of the ODEs are: 1) that I require differentials to be explicitly defined (but they can be defined in terms of other...
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    News How far should the Dragnet reach.

    I was referring to the IRS targetting Tea Party organizations with harder reviews to grant them non-profit status (which came out a few weeks ago), which chills their right to freely associate and gather funds, by taxing the funds they raise for a protected reason. Lol. Okay, we can make an...
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    News How far should the Dragnet reach.

    Seriosly. I mean, has it been too long for people to remember the IRS targetting the Tea Party? (Note: I *don't* support the Tea Party. But I do support their right to exercise their rights. There's a big differece.) That is proof alone that the government has no qualms with violating (or...
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    Python Overlapping Matches Python

    Yeah, I figured out that algebraic expressions are context free rather than regular. I think lex is used for context free languages. Would it be easier to get lex to do this than to write my own?
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    Python Overlapping Matches Python

    I'm writing a function to take a string like "aXYb" and return a regex in which the lower case letters act like actual character and the upper case become free variables. The regex generated from "aXYb" should match anything of the form a([a-z]+)([a-z]+)b. It does. But not exactly as "freely"...
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    Culture for microscope fun

    Sounds like fun. My last final is Friday, so I'll start over the weekend. I like how this is a long term, evolving project with multiple aspects of biology involved. Not only the "ooo look cool little cell things" that I was originally intending, but also a good example of ecology. Thanks for...
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    Python Trouble understanding recursion (Python)

    That's what it looks like to me. Have you ran it?
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    Culture for microscope fun

    Hi, so I have a little background in biology. I took AP bio in HS and got a 5 and really enjoyed it along the way. I got a microscope for my own amusement and also to maybe spark an interest in my little brother. What I'm having trouble with is finding good densities of moving microorganisms...
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    Need a cool function with this domain:

    Same is true of e^x and I'd say it's a lot more interesting than that. :)
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    Commutator subgroup.

    1) Find the commutator subgroup of the Frobenius group of order 20. 2) I have the Cayley table. 3) What is the definition of a commutator subgroup? I am absolutely sure we haven't heard this term all semester.
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    Best common-LISP IDE around?

    I don't know if it supports it, but Dr. Racket is good for Lisp like languages.
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    Set malloc's memory area

    Threading in C++ is still pretty awful. The program makes a list of primes. The parent maintains the list and forks off a child for each number to be checked and the exit status of the child indicates the primality of the number. The problem I'm having is that the parent writing back primes to...
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