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Comment More of a desk reference than a novel... (Score 1) 381

As many above have pointed out, there is little reason to read the entire series "like a novel" from cover to cover, in addition to the fact that yeah, it would take a while to WORK through it like a textbook as opposed to read through it quickly to see what is there. And yeah, there are better books now in profusion on many of the topics covered, although AFAIK there is no book or book series that is as encyclopedic on the subjects he covers.

However, many people will find some of the sections very useful. I personally found "Seminumerical Algorithms" useful indeed when learning about random number generators and testing random number generators. It isn't the last word, and it certainly isn't the latest word as we move into a 64 bit world and beyond, but it is an excellent starting point. In other parts of the series there are other gems or nuggets well worth studying or reading, even if you move on to actual research papers or better books afterwards.

To sum up, it is a useful thing to own if you are doing a lot of very widely spread code development and need to acquire literacy quickly in subjects it covers, even if you are going to end up looking for an O'Reilly text on some of those subjects to get a more modern perspective. Those OR books are probably going to reference, rewrite, and augment Knuth.

Note well that I'm an Old Guy (tm) and actually did write a lot of code in Fortran once in the long ago before abandoning it for C and Unix and beyond. TAOCP was one of the ONLY really good encyclopedic references for people who were NOT CPS majors and who needed to learn about algorithms of one sort or another or some aspect of coding covered in one of the many CPS courses they never took. They (I) didn't need a course with the best textbook of the day -- we needed to get started. Once started, we knew how to learn and go beyond the start. 1.5 cubic feet of shelf space wasn't too high a price to be able to learn something about everything or anything to get started.

Comment Re:It helps the economy too (Score 2, Interesting) 351

Damn skippy. If they are going to do this, they need to start -- start -- 3 to 5 years ahead by requiring ALL small motors to be built so that they can run on ethanol. And bear in mind that there are other problems with ethanol-laced fuel, the biggest one to my own experience being that it sucks water right out of the air and into your fuel tank. Alcohol is hydrophilic. Gasoline is hydrophobic. Put them together and you get the worst of both worlds -- a gas tank that builds up water in the bottom just sitting there in normally humid air.

Then there are the various parts in small motors that dissolve in ethanol.

Could this all be fixed? Sure, I imagine so. Not so sure about how the water issue can be fixed, but at least the engines can be designed not to break if you use ethanol either for timing reasons or because your fuel system turns into sludge while it operates. But they're not. So I'm left having to pay for no-E gasoline at a premium price from one of the few stations that carry it just to mow the lawn, run my chainsaw, run my boat, etc. This isn't just about cars.

Comment Re:BTW (Score 1) 145

Like or loathe him, it's hard to argue that Trump hasn't been one of the most influential people of the year.

In what way? The only thing I can think of is blowing an extraordinary amount of hot air. Extraordinary is in italics because he's US politician in an election year, so a very high bar has been set by his co-competitors in the hot air stakes. Yet he didn't get just beat them. He clobbered them so hrd they still don't know quite what happened. It was an amazing performance. It's what got him elected and deservedly so.

But influential? He's done nothing beyond telling us what he is going to do. Given that changes day by day to the point of being self contradictory I don't see how anybody could overly influenced by the literal meaning of the words. The underlying message that appealed to the voters must have worked at a much deeper level than specific promises. I've seen many articles theorising on what that message might have been, but few agree and none are convincing. I struggle with the idea that an entire nation could be influenced by an idea nobody can describe. So far his main influence is hold us spellbound, waiting and wondering what his first concrete moves will be.

If he really does jail Clinton, build a wall across Mexico and whatever else he has promised, then yes he will deserve the "person of year award". Probably "man of the century" as well, when the time comes. ("man" because this "person" crap is another piece of unnecessary PC that needs fixing and if he delivers on even 1/2 his promises he's just the man to fix it).

Comment Re:You can't (Score 1) 1321

You are right, unless the voter can visually verify THE ACTUAL PAPER that gets stored, the system can be hacked. And you are absolutely right that N boxes per state if not per precinct should be RANDOMLY (using e.g. actual dice, not electronic random number generators that could be tampered with) selected for quality control, opened, and checked for accuracy to within some very small tolerance. In the case where users are TOLD that their votes are not valid and they have the instant opportunity to correct to obtain a valid vote and then check it, tampering would involve tampering with the ballot box itself AND matching tampering with the machine, and that's a problem we always have, presumably controlled by honest and bipartisan representation in the polling officials.

I'd suggest not actually putting the paper in the hands of the voter, but letting them see it inside a glass screen right before it either spits it out or deposits it in the box, where they can SEE it go into the box, or do it over if it isn't valid or they accidentally voted for the wrong person somewhere.

Comment Re:You can't (Score 1) 1321

I replied above, or I'd mod you up. I completely agree. Paper trail, consistent right down to the fingerprints of the voter (should it come to it) on the paper form is not orthogonal to electronic counting. I'd even throw in a REQUIREMENT that actual dice be used to select a random sample of machines from each state to be opened and audited whether or not there is any evidence of tampering. ANY machines that give the wrong total outside of very, very narrow tolerances (determined by the empirical study of ballots that are incorrectly filled in etc) should trigger a statewide, or at least precinct-wide audit.

This isn't about this election, by the way. It is about "elections". I honestly believe that the polling officials at most polls in America are honest and patriotic and take their job as the guardians of democracy very seriously. No American who values free and honest elections should oppose ensuring that the system of voting itself is difficult to tamper with and self-auditing. Penalties for gaming the system should be extremely severe, and any court-admissible evidence that a candidate or party has actively participated in suborning the process should be grounds for overturning the election and forcing either a do-over, this time with the open door closed, or if the candidate is involved and a court so determines, both loss of the election EVEN IF THEY WON and felony jail time so that they can never run for public office again.

Comment Re:Spurious correlations (Score 1) 1321

Please. You can audit the software, and the networks, and the process of preparation. The problem is that software audits have ALREADY demonstrated that the machines can be hacked. There may well be direct evidence that they HAVE been hacked if one audits their internal firmware, and this could easily be done and wouldn't even be that expensive.

If one finds even a single machine that has been hacked, of course, chaos ensues. The founding fathers never anticipated this. The only fair thing to do would be to go back to the precincts and either hold an open re-vote or limit a re-vote to people who actually voted in the original, this time with paper ballots and a crowd of poll-watchers, but I don't think the constitution has any provision for this; at best the courts would have to order it in the absence of law or precedent. And "fair" isn't the standard "prescribed in the constitution" is.

But if there were clear evidence of tampering in these states -- really clear evidence -- if Republicans challenged both the clear evidence that Clinton won the popular election by a solid margin AND the clear evidence that the election in key "battleground" states was tampered with in favor of Trump (possibly with evidence of who did the tampering) then they'd be well advised to either concede the election in the electoral college (in exchange for keeping Trump actually out of jail) or at the very least, replace Trump with somebody centrist, that is to say NOT with Mike Pence. Maybe McCain. Even Ryan, although it isn't clear how centrist he really is. Or one of Trump's primary opponents that the Dems could live with. Otherwise they would face the mother of all backlashes in the next elections, forever.

Comment Re:Spurious correlations (Score 1) 1321

Richer precincts are more likely to have e-voting machines. Richer precincts are also more likely to lean Republican. Therefore, precincts that have e-voting machines are more lean Republican.

It's odd that you would say this, given the almost perfect polarization between urban, educated, rich precincts that almost without exception voted for Clinton and the rural, comparatively poor, precincts that voted for Trump. It is also something that is easily controlled for. The problem is that they compared counties with SIMILAR populations and the ones with voting machines produced a 7% surplus for Trump. Fairly consistently. This is not only not expected, it is (given a consistent pattern over many such counties and precincts) almost impossible, statistically. Yes, correlation is not causality, but at some point the p-value of the null hypothesis of an unrigged election goes to zero, independent of glib explanations like this one.

Comment Re:Popcorn time! (Score -1, Flamebait) 1321

Note well that the issue isn't that Trump won counties. It is that when one compares counties that are side by side and demographically similar, Trump won by an average of a 7% margin HIGHER only in those counties that used electronic voting machines. 7% is, frankly, an enormous factor given the large populations involved. But that isn't the problem. It is the p-factor. What is the probability that this PATTERN of events is due to random chance variations?

Here it is a no-brainer. The p-value for the null hypothesis "The election was fair" is basically zero, if there is a 7% marginal difference between electronic and non-electronic voting that is almost entirely biased in one direction. You don't even have to do a computation -- p has many zeros before the first 1, especially if the pattern persists over three different states, even more so if they are the CRITICAL states, even more so if they are states where polling before the election consistently got an entirely different result that would almost perfectly be explained by the 7% surplus.

What this is really saying is that there is almost no STATISTICAL doubt that the election was tampered with on a grand scale. The only remaining questions are: Who are the perpetrators (I personally doubt the RNC who honestly wouldn't dare, but somebody in Trump's campaign, a group of Trump-supporting hackers, or the Russians are all plausible alternatives, with IMO the Russians being way, way at the head of the line) and Did they leave behind any hard evidence of the exploits? It is going to be difficult to sell a statistical argument, no matter how compelling, to a population that doesn't even know what a p-value is, but any hard evidence at all of an exploit of even one machine would be enough to create constitutional chaos. Any evidence that tied the exploit to (fill in the blank) some specific group would lead to an overturn of the election, maybe even the election(s) (down into the Senate and House and state offices). Any evidence that ties in either the Russians or anyone at all in Trump's campaign will spark a large scale congressional investigation and, quite possibly, prosecution for treason of all involve in the one case, and a SERIOUS, GLOBAL escalation of tension in the other. You almost have to hope that it is an anonymous group just because of the danger to the world if it is the Russians and the damage to the country if it is any Republicans in or outside of Trump's campaign.

At the very least, the congressional investigation will open up Trump's true financial situation and start looking for hard evidence that he is controlled, financially or otherwise, by the Russians. For example, do they have evidence of him having sex with (fill in the unsavory blank)? Do they hold enough of his business debt that they can bankrupt him overnight? Is Melania his handler? His behavior towards the Russians has been "peculiar" throughout his campaign. This would explain a lot.

Comment Re:Good journalism is like middle class prosperity (Score 4, Interesting) 624

Once Trump became the leading Republican candidate, they were writing "analysis" headlines questioning their obligation to neutrality.

No they weren't. They were questioning the reporting style they had used for decades - the one where give the appearance of fairness by treating statements from both sides with the same respect. So when Trump said "If I will get rid of Obama care", they gave that the same weight as Clinton saying "I will keep Obama care". And they treat Trump's claim that "Obama wasn't born in the US", as they give to Clinton's view that "Obama was born in the US".

The practice of giving both sides equal weight has always been questionable. I am left scratching my head when I see a reputable news outlets give the same weight to and anit-vaxer's claims as they do to a professor of virology, and later defend it in the name of fairness. Nonetheless, they seemed to be firm believers in the process - until Trump came along. He made it utterly untenable to treat the pronouncements of both candidates identically.

Comment Sanity check... (Score 1) 247

OK, lessee, 60 mph is 26.8 m/sec. To go from zero to 26.8 m/sec in 2.4 sec requires an acceleration of 26.8/2.4 = 11.17 m/sec^2. g = 9.81 m/sec^2, meaning that it has to accelerate at 1.14 g.

The only force that can accelerate it is the frictional force from its tires. The maximum force of static friction (under ordinary circumstances, like ordinary tires and ordinary roadway) is f_s = \mu_s mg, producing a maximum acceleration of a = \mu_s g, so \mu_s would have to be 1.14 in order for this to be possible. This is well above the maximum for ordinary tires. So in order for your Tesla to do anything but burn rubber, you'd have to invest in some pretty serious racing tires capable of exerting an acceleration force greater than the weight of the car.

Comment Re:Fascinating stuff... (Score 1) 52

Anyway, tidal forces are indeed responsible for things like tidal locking of the moon (where the moon's slowing down was compensated by a change in its orbital distance and smaller effects on the axial rotation of the earth) but I don't see how it can tilt the rotational axis of a planet. Certainly the sun's tidal force at that distance is nowhere nearly strong enough, or is it?


I guess that together, they are! The moon and sun exert an AVERAGE TORQUE on the Earth, and it is large enough to cause the axis to precess! This effect is also very dependent on things like mass distribution -- ice ages rearrange substantial surface mass and can indeed alter the tensor moment of inertial and hence cause the axis of rotation itself to move relative to the not-terribly-solid earth, with interesting consequences, see:

especially: "The redistribution of ice-water on the surface of the Earth and the flow of mantle rocks causes changes in the gravitational field as well as changes to the distribution of the moment of inertia of the Earth. These changes to the moment of inertia result in a change in the angular velocity, axis, and wobble of the Earth's rotation.

The weight of the redistributed surface mass loaded the lithosphere, caused it to flex and also induced stress within the Earth. The presence of the glaciers generally suppressed the movement of faults below.[72][73][74] However, during deglaciation, the faults experience accelerated slip triggering earthquakes. Earthquakes triggered near the ice margin may in turn accelerate ice calving and may account for the Heinrich events.[75] As more ice is removed near the ice margin, more intraplate earthquakes are induced and this positive feedback may explain the fast collapse of ice sheets."


Comment Re:Angular momentum (Score 2) 52

Not to go into this in complete detail, but:

a) The moment of intertia is a tensor, not a scalar like you learned (maybe) in Intro physics. So lots of motions -- like a skater extending just ONE arm out well above her center of mass -- are going to alter the axis of rotation. This is why it is important to balance your tires -- to keep the 'natural' axis of rotation identical to the physical axis of your car's bearings.

b) A moon exerts a torque on the planet it orbits. If the moon isn't perfectly in the ecliptic plane with the sun or if there is any bobble, not just the magnitude of the angular momentum varies, but the direction too. This is why the Earth's axis precesses -- it is tilted relative to the average direction of these torques.

So maybe the physicists who published the article(s) and their referees aren't actually incompetent. Just sayin'...


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