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Comments

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An Air Traffic Control System For Drones

Lisandro Re: IKR? I'm sick of our hobby being lumped in w/ (77 comments)

We (the responsible R/C helicopter community) have been asking, in fact begging, for regulation for some time now. Even going so far as to have pseudo-regulation via AMA. Unfortunately the FAA has continually put the issue on the back-burner....

I'm aware of this. Sadly, this won't change until there's money involved, like Amazon's recent research on using quads for package delivery. These regulations are strict and hard to change, but, again, there's good reason for it.

Also, the analogy of radio-controlled cars is absurdly non-sequitur as cars are 3,000lbs of steel/aluminum and multi-rotors are 27 oz. of plastic/carbon fiber.

The thing is, you don't need a lot of mass to damage something that flies. A RC car can wreck havoc if stepped over by a car going 70MPH on a highway, just like a quad can do even more damage if sucked into the jet intake of an airliner / helicopter. Or the propeller / attack surfaces of a small airplane - incidents with birds, for example, are sadly common.

yesterday
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An Air Traffic Control System For Drones

Lisandro Re:IKR? I'm sick of our hobby being lumped in w/ (77 comments)

That's right, these people are just pretending they're in a real helicopter. IS that so wrong? I mean the stuff of little boy dreams is now possible.

It is if you get in the way of an actual manned helicopter. If drone/RPV usage keeps going up regulation will be needed, sooner or later. A good part of a private pilot license exam is regarding regulations and air traffic rules. Even if you only plan to spin around a runway in a small Cessna these still apply.

Imagine what would happen if people started putting radio controlled cars in a highway. Now imaginge the highway is 3,000FT above the ground.

2 days ago
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Where Intel Processors Fail At Math (Again)

Lisandro Re: Exact mathematical value isn't the ideal (238 comments)

They aren't. When you start adding up a lot of cents you end up, invariably, with rounding errors. FPs are not intended for this task.

The way they intended to deal with this issue back then was to round down results to x decimals, just to make sure the clients weren't charged extra. And even that wasn't enough.

about a week ago
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Where Intel Processors Fail At Math (Again)

Lisandro Re:Exact mathematical value isn't the ideal (238 comments)

Ditto. Not only that, i'm amazed by the number of programmers who don't properly understand floating point arithmetic either.

A long time ago i had to write a C/C++ fixed-point arithmetic library for a (major) telecom company because their billing processes would routinely output totals with cent errors; over a full year these added up to a significant ammount of money, a-la-Superman III. No one even had a clue of why their processes failed.

about two weeks ago
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Where Intel Processors Fail At Math (Again)

Lisandro Re:Exact mathematical value isn't the ideal (238 comments)

Some idiot researcher who expects Excel or an FPU instruction to be accurate for sin to more than 10 decimal places is going to crop up SO MANY anomalies in their data that they'll stick out like a sore thumb.

Unless the processor's documentation explicitly promises that accuracy.

about two weeks ago
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BitHammer, the BitTorrent Banhammer

Lisandro Re:Alternative headline (428 comments)

Because I have every right to use the network as the guy making it impossible for me to use it.

Then, by your own logic, you're not justified to use bithammer. I hate to play the devil's advocate here, but OzPeter makes a damn good point. If a BT user really prevents you from feeding your family then you should consider an alternative other than McDonalds in the first place.

about two weeks ago
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Microsoft Won't Bring Back the Start Menu Until 2015

Lisandro Re:Many users won't be back (516 comments)

I was actually being facetious, but this is not far off from the truth. Nokia was already hurting when iOS and Android gained momentum, but it really took a nosedive pretty much the second the decided to support Windows exclusively.

A crying shame, because they sell some very nice hardware.

about 5 months ago
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Microsoft Won't Bring Back the Start Menu Until 2015

Lisandro Re:Many users won't be back (516 comments)

Look at Nokia. Those phones will only be able to access the Microsoft cloud.

That nicely explains Nokia sales figures lately. Something like 30% down this last year.

about 5 months ago
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PHP Next Generation

Lisandro Re:PHP? (213 comments)

sigh...

Whatever kid. You win. I have actual work to do.

about 5 months ago
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PHP Next Generation

Lisandro Re:PHP? (213 comments)

In ways you cannot undersand, evidently. The distinction on C when comparing type-casted operands is precisely because casting is guaranteed to destroy precision - operands are effectively modified in the process. This has NOTHING to do with the way relational operators work: they behave in a sane way, like they do in every other language on Earth.

Now contrast that with the idiotic PHP decision of setting rules for relational operators leading to circular logic. I know the "this might fool the typical PHP developer" warning went over your head, but ponder on this: on my original PHP code snippet, where's the "loss of precision"?

Where's the casting?

Hell, where do you apply your "object has precedence" mantra on it?

I really can't believe that someone could not only defend this madness so vehemently, but also without really understanding what he/she is talking about. Try a new language, son. It will open your horizons.

PS: I'm a he, not a she.

about 5 months ago
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PHP Next Generation

Lisandro Re:PHP? (213 comments)

Just like PHP!

...sigh...

Just like PHP, where comparison operators are transitive except in cases where precision is lost in type-casting of operands.

Yeah. I'm dying to know what the "loss of precision" is when comparing a float to an array to an object.

No, you know what? I don't. Go have fun with your toy websites.

about 5 months ago
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PHP Next Generation

Lisandro Re:PHP? (213 comments)

Dude, you are the one who's flat out wrong. Not only C has transitive relationship operators, but the language specification actually states that value comparison operators must be transitive except in cases where precision is lost in type-casting of operands.

So, for example, this might fool the typical PHP developer...

int main(void) {
unsigned long a = 98765UL;
int b = -12345;
short c = 1;

if (a < b) printf("a < b!\n");
if (b < c) printf("b < c!\n");
if (c < a) printf("c < a!\n");
}

...while you're simply rounding off (modifying!) operands in the process. This can be easily show by controlling how casting is performed:

int main(void) {
unsigned long a = 98765UL;
int b = -12345;
short c = 1;

if (a < (long)b) printf("a < b!\n");
if (b < (int)c) printf("b < c!\n");
if (c < (short)a) printf("c < a!\n");
}

Compare this to the brainfuck that is PHP, where comparison rules are well stablished but still manage to produce this crap. I can't believe i'm actually discussing this.

about 5 months ago
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PHP Next Generation

Lisandro Re:PHP? (213 comments)

No, it should not be complicated. It does not make sense - PHP is the only, and i mean only language i found with comparison rules that are non-transitive. And even worse, circular.

about 5 months ago
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PHP Next Generation

Lisandro Re:PHP? (213 comments)

Because it's a language that others are likely to already understand. PHP is also written in C, which likely influenced the language.

So are Python, Perl, Ruby and Java, and you won't see anyone comparing them to C. That's a poor argument.

about 5 months ago
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PHP Next Generation

Lisandro Re:PHP? (213 comments)

Oh, and by the way. Why do people insists on comparing PHP to C? Isn't PHP supposed to be a high-level, website oriented scripting language?

I ask because i've seen bugs about PHP segfaulting reliably rejected only because "this behavior is consistent with what lower level languages like C do". It's like watching an exploit slowly growing from its infancy.

about 5 months ago
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PHP Next Generation

Lisandro Re:PHP? (213 comments)

I see. You're just confused by dynamic languages. Try the same operations in C, with the relevant casts, and note the results. Hey, look at that! Not quite so "nonsensical" now, is it?

Like I said, give that article a good fact-check. You'll regret ever recommending it.

"Dynamic languages" eh? Show me a "dynamic language" where i can do this (blatantly stolen from this site):

$ cat circular.php
<?php
 
$a = INF;
$b = array();
$c = (object)array();
 
var_dump($a < $b);
var_dump($b < $c);
var_dump($c < $a);
 
$ php circular.php
bool(true)
bool(true)
bool(true)

You're right though. Nonsense confuses me.

about 5 months ago
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PHP Next Generation

Lisandro Re:PHP? (213 comments)

Really? Most, if not all of it, is stuff i've ran into in the past. The nonsensical comparison operator results and the so-called "arrays" pop into my mind right now...

about 5 months ago
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PHP Next Generation

Lisandro Re:PHP? (213 comments)

get a life.. for real. Always easy to play MMQB, harder to actually *do* something.

I've worked with PHP and its assorted web frameworks enough times to completely relate to what that site tells.

That an amateur language like PHP holds 80% of the web marketshare seems insane until you actually realize that 80% of the web is hardly professionally developed either.

about 5 months ago
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Heartbleed Coder: Bug In OpenSSL Was an Honest Mistake

Lisandro Re:Not malicious but not honest? (447 comments)

Ditto. Writing a custom malloc is insane for a sensitive security library like this... specially when it is done so carelessly.

The fact that OpenSSL won't even work using regular malloc() suggests that there're more issues waiting to pop up here.

about 6 months ago

Submissions

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Pixar's RenderMan is now free for non-commercial use

Lisandro Lisandro writes  |  about 5 months ago

Lisandro (799651) writes "Pixar's RenderMan, the de-facto industry standard for the creation of CGI on movies, has announced a price restructuring. Licences are down to $495, but the kicker is that non-commercial users are now able to use it for free."
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Java 7 ships with severe bug

Lisandro Lisandro writes  |  more than 3 years ago

Lisandro (799651) writes "Lucid Imagination just posted an announcement about a severe bug in the recently released Java 7. Apparently some loops are miscompiled due to errors in the HotSpot compiler optimizator, which causes programs to fail. Apparently this bug impacts several Apache projects directly — Apache Lucene Core and Apache Solr have already raised an warning, noting that the bug might be present in Java 6 as well."
Link to Original Source
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German researchers claim to have found AIDS cure

Lisandro Lisandro writes  |  more than 3 years ago

Lisandro (799651) writes "Deustche Welle is reporting that Timothy Ray Brown, an AIDS-positive leukemia patient was apparently cured of his HIV infection after receiving a blood stem cell transplant in 2007. The study found that "the patient remained without viral rebound 20 months after transplantation and discontinuation of antiretroviral therapy.""
Link to Original Source
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German doctors claim to have found AIDS cure

Lisandro Lisandro writes  |  more than 3 years ago

Lisandro (799651) writes "Deustche Welle is reporting that Timothy Ray Brown, an AIDS-positive leukemia patient was apparently cured of his HIV infection after receiving a blood stem cell transplant in 2007. The study found that "the patient remained without viral rebound 20 months after transplantation and discontinuation of antiretroviral therapy.""
Link to Original Source
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Apple press release regarding iPhone 4 reception

Lisandro Lisandro writes  |  more than 4 years ago

Lisandro (799651) writes "Apple has just releases a letter addressing the signal issues a lot of users seem to be having with their iPhone 4. They claim to have discovered the cause for the drop in bars, which is "both simple and surprising" — a wrong formula used to calculate how many bars are displayed for a given signal strength."
Link to Original Source
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Man blames child pornography on his cat

Lisandro Lisandro writes  |  more than 5 years ago

Lisandro writes "A Jensen Beach resdient blamed his collection of over 1,000 images of child pornography on his cat. When confronted by the police, the man argued he used to leave his computer on and his cat downloaded strange material by walking on the keyboard."
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NASA to announce success of Long Galactic Hunt

Lisandro Lisandro writes  |  more than 6 years ago

Lisandro writes "In a cryptic press release, NASA has scheduled a media teleconference on May 14 at 13:00 EDT, to announce the discovery of an object in our Galaxy astronomers have been hunting for more than 50 years. All that was let known prior to the conference is that the finding was made by combining data from NASA's Chandra X-ray Observatory with ground-based observations. Keep in mind that NASA is roughly 50 years old."
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Shutdown day is dawning on us

Lisandro Lisandro writes  |  more than 6 years ago

Lisandro writes "May 3rd this year is Shutdown Day. So called the "one of the biggest global experiments ever to take place on the Internet", Shutdown Day aims to find out how many how many people can go without a computer for one whole day, and to get them to mull over how the increasing use of computers change their lives — for better or for worse."

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