This is exactly what I came here to say. Now I don't have to. It's hard for me to continue reading an article after reading such an obvious logical error.
No, the python interpreter itself takes about 0.03 seconds to start up on an i7. Awk and sed and friends are usually about 1/10th of that. So the python interpreter startup time dominates the cost for most simple tasks. It's not enough to notice when you're typing things by hand at the shell, but the difference can be painful if you're writing bash scripts. I use a similar python tool for command line work, but I always go for sed when I'm writing bash scripts that I plan to distribute.
"Some later interest was fuelled by Loyd offering a $1,000 prize for anyone who could provide a solution for achieving a particular combination specified by Loyd, namely reversing the 14 and 15.[13] This was impossible, as had been shown over a decade earlier by Johnson & Story (1879), as it required a transformation from an even to an odd combination."
It just vexes me that thorium research is not a national priority. How can a technology that, by many estimates, has at least a 50% chance of being a viable replacement of all energy needs over the next 1000 years not be worthy of the US investment? We lose hundreds of billions of dollars per year in oil imports. Why is that not worth avoiding?
Yes, the name is controversial. But it's also highly functional. I do recommend that you try out pythonpy even though you have already tried one of the other similar tools. I think you'll find it to be simpler, without losing much in terms of functionality. Also, the others haven't implemented ipython style tab completion from the command line.
fwiw, correlation actually is transitive if strong enough. This is obvious if corr(x,y) = 1 and corr(y,z) = 1, then corr(x,z) = 1. More generally, you can get this constraint by looking at the minimal value a for which the matrix [[1, corr(x,y), a], [corr(x,y), 1, corr(y, z)], [a, corr(y,z), 1]] remains positive semidefinite to find the minimal correlation of x and z given that of (x,y) and (y,z). I mention this because in this case the correlations may be strong enough so that the minimal a is positive, and because it's important to understand exactly when our intuition about transitivity of correlation breaks down.
Was just reading this interesting article and mentioned it to my girlfriend. She said this was old news and told me about a shampoo with seemingly bogus reviews. So I did some digging... Seems like there were some voting rings on this product too. Or maybe all three of these people just happened to be reviewing both Argan Oil Shampoos and iPhone 5 Battery Replacement's:
It's constructed entirely from builtin unix commands, so it's solid. The biggest risk is that someone could put malicious code into your ~/.sshrc, which would be run on the server. However, if they have write access to your $HOME directory, you're already in big trouble, as they could just as easily add something like `alias ssh='ssh "rm -rf $HOME"' to your ~/.bashrc.
yes, but using a separate scp command requires a second round trip and second password/key authentication, which would double the wait time of the already slow ssh login process.
np. The funny thing is that sshrc is just a bash script, so it really could have come about 10 years ago. All it took was a few weeks of unemployment and refusal to believe that it couldn't be done. For those of you that opt out of reading the source but are curious as to how it works internally: the tool zips all your files, dumps them as hex code, and stuffs them into an argument string for the little known ssh -t option, which carries instructions to undo the whole process on the server side. As a side note, stuffing a linux filesystem into an argument string is the reason why your ~/.sshrc.d can be much bigger than a megabyte - bash doesn't like processing commands that are that long.
Do my downvoters have any feedback? How can you deny that content dilution is a serious problem that can be ameliorated, but not solved by intelligent modding. YC has already recognized this by recently adding the separate "Show HN" section.
Of course you work hard, and thank you for that, but you're fighting an uphill battle. It's not like all the submissions are coming from YC founders anymore. People love to post stories with these sensational titles and meager content, and other people like to upvote them. There are still a lot of great posters/commenters here on hacker news, which is why I still come back occasionally, esp. for casual browsing. But the userbase is quickly being (has quickly been) diluted, and there is no protection from these goons by stricter posting rules like on subreddits. That's why I've started to go to /r/programming instead when I want to learn something. All this non-intellectual political content drains my energy. Just my two cents.
Oh, oops. I was reading their statement:
This interpretation is incorrect
without the additional hypothesis that V (x) is
a one-to-one function.
as - all of the phi functions must be one-to-one. Looks like they made the same assumption that I would have.
This was bothering me though so thanks for your response.
Am I missing something or is the author of this pdf's proof equally flawed. They assume each function is idempotent and injective ... meaning that it is the identity function. And the proof doesn't follow. A much more natural way to have "fixed" the original proof would be to require that V: X -> R be injective.
Yea, haha. Reminds me of a time when I was a kid, and a friend of mine hadn't learned much about the four mountains surrounding Tucson. When I told them their names, he said, "Wow, they named them after the high schools."
I was in Shanghai last summer and started crossing the cross-walk with cars approaching from both directions. Instead of slowing, the cars just started honking and racing towards me. Had to play some hardcore frogger to cross the street. Just goes to show that driver opinions really are different in China. Oh, and don't use the crosswalks.
Yea, it's really tough to find an analysis course. I looked around online for a long time and never found one. Ended up picking it up as a regular college class and learned a lot. I don't understand why nobody has bother recording analysis lectures and posting them as they have with other subjects. It seems the only autodidactic way to learn analysis at this point is to download a book and dive in. If you're looking for pure math though, http://www.extension.harvard.edu/open-learning-initiative/ab... is a really great Abstract Algebra course taught by Gross at Harvard though.
Yea, right... You can't apply math to public policy - only stories and soft science. Math is absolutely useless because it's abstract and ... "fictional".
"At this point I asked myself, 'is it really that easy?' I then thought about the two newly discovered vulnerabilities and realized both were in the administrative interface after authenticating as the administrative user. I needed to have the same preconditions as the attacker. So I tried to find vulnerabilities without using any of my access credentials."
You're missing the forest for the trees. The fact that some people's utility function supports not stealing by default is irrelevant to the structure of the game. It's still a prisoners dilemma and the existence of the police is justified in its efforts to modify the game's structure.
Police are not supposed to be a net good. They are a classic solution to a game theoretic prisoner's dilemma. If there were no enforcement of laws by police, it would be in everyone's best interest to e.g. steal. Regardless of whether other people steal, you'd be better off doing it. So as a classic solution to the prisoners dilemma, you introduce a force that strictly decreases everyone's utility function. How can this be a good thing? Well, because it changes everyone's optimal strategy from stealing to not stealing, reaching a global optimum. Now you'll notice that this strategy only improves things if it actually changes people's behavior. If people continue stealing anyway at the same rates, then things have only gotten worse (unless you subscribe to punitive, rather than deterrent punishment). So the primary purpose of police is deterrence through the threat of negative reinforcement, not "helping people". Further, whenever police actually have to enforce laws, its a sign that something has gone wildly wrong. The deterrent didn't work, and things are worse off than if there were no police at all. Of course, in reality criminal behavior has a lot of motivators and it's not possible to change everyone's optimal strategy just by raising punishments, so you're going to have police enforcing laws. But there is no police department that is more successful than one where the police just sit around and do nothing.
Yea, Mao Ze Dong wasn't the same thing though. It's estimated as many as 60 million people died in China from hunger. Many others died from the civil war (Cultural Revolution). There may have been some genocide but the term doesn't apply as well as in Germany/Russia.
Yea, sorry about that. I had an initiative to make a windows version, wpy, a little after launch, but couldn't really get any windows developers interested in making it happen. From my time working on windows, I know this tool would be even more valuable there than on unix. I'll try to find a place to indicate this doesn't work. Perhaps there's a good way to check if the system is windows in the setup.py and warn users.
Yea, fortunately pythonpy supports lazy iteration over sys.stdin when you really need it. Just like in python, the syntax won't be as nice as using a list. But it works:
However, the number of times that you need this are surprisingly rare. Most lazy operations don't require that each row be aware of the surrounding row context, and using the much simpler:
py -x 'new_row_from_old_row(x)'
will get the job done in a lazy fashion. Usually, when you need rows to be context aware, as in:
py -l 'sorted(l)'
or
py -l 'set(l)'
it's just not possible to accomplish your task without reading in all of stdin.