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Comment: data mining (Score 1) 421

by e**(i pi)-1 (#48730615) Attached to: What Isn't There an App For?
there should be an app which constantly reports statistics how much app information is transmitted to third parties. An other good app would be able to store of old versions of apps. My previously favorate note taking app penultimate recently got swallowed by evernote. The old version still allowed emailing the notes and keeping the notes private, now everything goes through the evernote servers. It was even no more possible to the old notes without going through the evernote servers.

Comment: checking for errors is crucial (Score 1) 226

by e**(i pi)-1 (#48725769) Attached to: Red Hat Engineer Improves Math Performance of Glibc
What will be important when doing optimization is that no errors are introduced. Having errors in basic mathematical routines can break things at unpredictable places. The worst errors are the ones which deal with exceptional cases which are rarely hit upon. We worked once on integer factorization algorithms [We programmed Morrison-Brillard and quadratic Sieve methods, and everything in the group had been written from scratch, even the large integer libraries were written from the ground up in Pascal by a relatively large group of programmers, not using a single line of code from the outside as probably custom in any military setup.] Suddenly, our factorization algorithms did not work any more reliably. Debugging took some time but we could pinpoint it to parts where square roots were used. Indeed, the square root routine in rings of integers had been optimized by the group working on fundamental routines. It was quickly fixed, but I can only imagine a rare error in an important library of GCC. In the current case, it looks however as if the engineer knows what he is doing. Especially implementing the squaring function separately is smart and I'm surprised that this had not been done already. When dealing with integer arithmetic like taking powers a^b modulo some number, it is well known to be best first to compute powers a,a^2,(a^2)^2 by successively taking square roots, then write b in binary form and cobbling together the power a^b as a product of the precomputation which is of course the reason why taking powers is cheap in integer arithmetic and important in cryptology like RSA. So, it is important to be able to square quickly.

Comment: speed is good (Score 4, Interesting) 194

by e**(i pi)-1 (#48675595) Attached to: MIT Unifies Web Development In Single, Speedy New Language
having on the server side fast and efficient code is nice but there are a plethora of webserver technologies out there and they can interact with virtually any programming language in the background having various technologies working together and having them developed indpendently has lots of advantages. Why bake everything together? Having sepearte entities (server, authoring language, scripting languages, databases) allows more flexibility. Efficiency and simplicity is nice but one can also overdo it. I learned real programming in Pascal, but Wirth soon started to develop the more efficient Modula, then Oberon flavors. Pascal started to stall. Oberon was great, everything, the compiler, operating system, everything fitted on one floppy. From the application and developer point of view it is a disaster to know that the shelf life of a programming language is only a few years, until the developer loses interest finds a better way to rewite the entire thing. This is especially the case for creative guys like Wirth. At one point, (oberon I) he even thought it would be nicer to have no FOR loop, as FOR loops leads to bad programs. Well, he had to reintroduce it in Oberon II. Academic elegance and theory not always goes parallel with the real world.

Comment: richter scale needed (Score 1) 64

by e**(i pi)-1 (#48464207) Attached to: The People Who Are Branding Vulnerabilities
Giving names is often part of propaganda. This is common in politics. No surprise that this happens in industries where lots of money is. Giving catchy names to vulnerabilities certainly was effective to raise awareness but once the storm is over people care even less or become immune. Especially if propaganda is evident, it does not work any more. Heartbleed was serious, but totally over hyped by the media, with poodle it worked less, with shellshock it was already pathetic Its best to keep being informed by trusted sources like Cert. What would be nice to know is a scale analogue to a Richter scale in earthquakes with a well defined gauge, taking into account how much damage the bug or malware has created, how many systems were affected in total, taking into account also a relative number.

Comment: deja vue? (Score 1) 745

by e**(i pi)-1 (#46261841) Attached to: Mathematician: Is Our Universe a Simulation?
Hmm. A Deja vue. A glitch in the matrix? Seriously,such ideas are already a cliche. It had already been subject to fascinating contemplations in Hofstadters book of 1981. And progress in virtual reality and computer games since then have only amplified that the idea of a simulation would be hard to detect.

Comment: reason why calculators still exist (Score 1) 340

by e**(i pi)-1 (#44727957) Attached to: For Education, Why TI-83 > iPad
Of course, calculators are technically long obsolete. It is exactly their limitations is the reason why they are still around because they produce controlled limits on what the device could do, for example not access the web. With smartphone or tablet already, there is less control for the teacher. There are now apps like "myscript calculator" where one can handwrite formulas onto the screen and it evaluates it. The article still has a point. With calculators, one could still experiment. I had hacked my TI 59 so that it featured a joy stick and use it to control the lights of my room. Also not well known was that it was possible to reprogram the basic functions on the calculator like allocate the sin button to something else. Presumabely this made it cheaper for TI to sell specialized versions of their calculators but the backdoor key combination to allow such mods had not been documented anywhere. (here are pictures of my highschool machine:

Comment: BYOD is doomed for tests (Score 1) 55

by e**(i pi)-1 (#44529857) Attached to: Finland's Upper Secondary School Exams Going All-Linux
I believe, BYOD is doomed from the beginning, thats why graphing calculators (dinosaurs in comparison with modern smart phones) are still around: because of their limitations they can still be used for tests. Many questions for systems running on students hardware? How is the live system booted: DVD, memorystick? How does that work on a tablet? The biggest weakness is that the system is booted in a subsystem of an other OS. If the system interacts with a server, how do you prevent other internet access? How do you prevent other programs to be run? One major weakness for math testing systems accessed from a browser is that students can "google" or "alpha" the answer. Many system run the clock on the students system so that if the student runs a virtual machine and stops it, the clock stops. For testing systems with BYOD, there is always also the danger that the test leaks. Even with a completely locked down system, it is difficult to prevent that a student boots the OS in a virtual machine and have free range and post the test on the web. It needs only one student to do so. A test examinator can not see the difference (without considerable effort) whether the machine has booted up in a virtual machine or not. Ie only safe way to make a safe and accountable testing system is to make it on paper.

Comment: relative (Score 0) 250

by e**(i pi)-1 (#43021103) Attached to: Cryptography 'Becoming Less Important,' Adi Shamir Says
The quote was clearly understood "relative to other measures". Besides that one has to keep in mind that the top experts are often wrong. Look at some quotes:
  • Everything that can be invented has been invented
  • Who wants to hear actors talk?
  • There is no reason anyone would want a computer in their home.
  • The bomb will never go off. I speak as an expert in explosives.

Comment: we need a tablet emulator (Score 1) 179

by e**(i pi)-1 (#42954835) Attached to: Ubuntu Tablets: Less Jarring Than Windows 8?
Certainly good to add more variety. For me a tablet is like a monitor. It just has to work and not do more what it is asked for, like user tracking or information collecting or content change or adaptation. What would be nice is to have an emulator application on a desktop which looks and behaves from the outside like a tablet. In a time, when news outlets or search engines more and more also adapt their pages to the medium (never mind the look and feel, the disturbing part is also change of content), it would be good to have a tool, which allows to catch possible leaks and see what is done when a "tablet" is recognized. Changing the user agent in the browser can not do that yet.

Comment: use (Score 4, Interesting) 274

by e**(i pi)-1 (#42850267) Attached to: GNU Hurd To Develop SATA, USB, Audio Support
Why does anything always have to do with practicality or use. Tinkering with new or old operating systems can be compared with learning and messing with new or old math or physics. I guess that when developing some USB drivers for hurd, you learn more than improving a given drivers for linux. The later is like reading and understanding and improving on a paper which is "well known", the former like breaking new grounds.

Comment: Re:Wait, what? (Score 2) 379

by e**(i pi)-1 (#42724053) Attached to: Perl's Glory Days Are Behind It, But It Isn't Going Anywhere
Second that. Perl is great exactly because it is stable, reliable and because of the prospect that it will remain so. Like the Unix shell, Latex or plain old C. Its maybe as close as one can get to mathematical tools, which by default never change. A language has to earn the status of being archane. Thats when it can be used also within larger projects without worry that basic functionality is depreciated. Its not an exclusive or. The world needs both, new languages which are exciting but change often and old languages which have a track record of being robust.

Comment: Re:There people are really, really stupid (Score 1) 309

by e**(i pi)-1 (#41616659) Attached to: US Looks For Input On "The Next Big Things"
But any attempt to plan and direct breakthroughs will only serve to prevent them.
What about nuclear energy or getting to the moon? These were planned and heavily directed breakthroughs.
Breakthroughs cannot be planned
Is this really true? Modern industry is full of examples where breakthroughs have been planned.
You can put a whole lot of smart people to work, give them everything they want, and maybe you will get lucky.
Isn't this also a form of planning? Maybe we should say that breakthroughs can not be micromanaged.

"We shall reach greater and greater platitudes of achievement." -- Richard J. Daley