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Comment: Re:Quite accurately? (Score 1) 170

by spitzak (#47886191) Attached to: Universal Big Bang Lithium Deficit Confirmed

The model can give a "quite accurate" expected value, even when wrong. Example (note numbers are completely made up):

Say there is model A which predicts 2.5-2.6% lithium.

Say there is another model B which predicts 2%-8% lithium.

Say in reality there is 1% lithium.

Both models are apprently wrong. But Model A is more "accurate" in making the wrong prediction. Therefore the text in the article is perfectly correct.

Get it?

Comment: Re:Empirical Data Trumps Information Theory (Score 1) 211

by spitzak (#47874933) Attached to: Information Theory Places New Limits On Origin of Life

Actually it will be a lot worse than Venus and due to a different cause in that the sun would actually be irradating many times more energy on it, and possibly even engulfing it in hot plasma. Venus is heated by the insulation of a huge amount of CO2, the Earth with that much CO2 would be equally hot, and Venus without it would be just a tropical Earth. And when the sun expands the CO2 will be irrelevant (I would think the heat would actually make it escape to space), not that that is going to help any.

Comment: Re:Can someone clarify the state of BitCoin? (Score 2) 134

by vadim_t (#47863271) Attached to: Paypal Jumps Into Bitcoin With Both Feet

It's risky of course, but it has its upsides. Eg, here's an ID:


If you want to buy me a beer, it's easy. No need to exchange personal information, mess with bank transfers, or anything of the sort. I can accept payments without even making any preparation -- install the client, generate the ID, figure out how to get the money later. That's the sort of thing where I think it does great -- allowing the near equivalent of just buying somebody a beer in person, but through the internet.

For large amounts, yes, you better be careful, and be willing to take the risk.

Comment: Re:Can someone clarify the state of BitCoin? (Score 2) 134

by vadim_t (#47863191) Attached to: Paypal Jumps Into Bitcoin With Both Feet

Yes, but:

You buy 0.1 BTC at $500/BTC. Later you buy 0.2 BTC at $550/BTC. Later you buy 0.2 BTC at $560/BTC. Your client will say you have 0.5 BTC, but internally there actually are 3 separate accounts that it'll handle transparently. If you pay 0.3 BTC to somebody, it'll have to issue payments from at least two of them.

So, you wait a month, now it's $570/BTC, and sell 0.05 BTC.

My understanding is that it's perfectly possible that your client will decide to source bitcoins from all 3 accounts in some random quantities that add to 0.05. So how much have you gained? Hard to tell, since the standard client won't directly tell you what accounts it used, and doesn't know how much you bought each part of your balance for, it doesn't do banking at all.

Comment: Re:Can someone clarify the state of BitCoin? (Score 5, Informative) 134

by vadim_t (#47862855) Attached to: Paypal Jumps Into Bitcoin With Both Feet

I'm not exactly a guru of bitcoin, but I'll summarize as somebody who's tried it recently out of curiosity.

Getting into it is surprisingly difficult. Purchasing bitcoins right now (or before paypal maybe) is pretty hard. Near impossible to find a site that will let you buy with a credit card, because sellers get screwed over with chargebacks.

Mining bitcoin at this point isn't worth it. At all. A high end GPU working 24/7 would get you $10 per month while costing more in power. At this point mining is only profitable to people willing spend a lot of money on very specialized hardware.

Once you have some, it's easy enough to use. But it's an unregulated system, so there is some danger and no safety net. If you're ever going to put serious money into it, be very, very careful. Danger comes both from things like getting hacked, and from that the value fluctuates without any central control.

Tax-wise it seems tricky. It seems (you're nuts if you take advice from a random stranger on this) that it's considered an asset, and if bitcoin gains in value you have to pay tax on that. Up to you to figure out how to keep track of it and do it properly.

As far as working, it does. You can buy stuff with it fine, and the USD/BTC exchange rate is stable enough. If you have cash to spare it might be worth to get some, just in case it increases a lot in value (I doubt paypal would get into it without consulting a bunch of lawyers), but you'd be nuts to put your life savings into it.

Comment: Re:Powershell (Score 2) 729

Null-terminated strings were considered superior to using a length because they allowed strings to be > 255 bytes long (using 16 bits for the length would allow longer counted strings, but at that time with 4K of memory nobody in their right mind would suggest wasting a byte like that!).

Null-terminated strings also have the nice property that getting the "tail" is a very fast operation, since you just return a pointer to the middle. This meant that searches could return strings, rather than indexes. This then meant that every function that worked on text only needed one argument, a string, rather than two (a string and an index). The savings due to this were pretty significant.

Comment: Re:Programming: You're doing it completely wrong (Score 5, Interesting) 120

by spitzak (#47761275) Attached to: The Grumpy Programmer has Advice for Young Computer Workers (Video)

Actually more often I have seen the opposite: claims the new stuff is going to be faster, the compiler is not smart enough to figure out that they are the same, and thus you should use the new stuff.

There was a coworker who insisted that using C++ std::foreach for loops was faster because "the compiler knows you can't break out of it and thus can optimize the whole thing". I had two objections to this: first of all it would be a really stupid optimizing compiler that could not figure out there are no "break" statements inside the for loop. And second the C++ was still allowed to throw exceptions in both cases.

The other objection I had was that the functors were unreadable.

Yet another objection is my suspicion that the optimization would be far worse on the functors due to the enormous header files of templates they actually used and I expected the optimizer for the simple for loop to have fewer bugs in it. But I did not test this.

Comment: Re:Compelled to freely license? (Score 1) 191

by spitzak (#47658911) Attached to: Larry Rosen: A Case Study In Understanding (and Enforcing) the GPL

Copyright violation conviction results in having to pay monetary damages to the copyright holder, and to cease redistribution of the copyrighted work.

Fulfilling the requirements of the LGPL on new copies in no way is required by, and conversely also does not get you out of, the punishment. Therefore for every possible reason in the book this "viral" idea is false.

Just because he's dead is no reason to lay off work.