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Comment: Re:Kids don't understand sparse arrays (Score 1) 126 126

It all depends on what you want to do with your matrices. Various operations have various costs in different sparse matrix formats. The standard ones are COO or coordinate format: a list of triples (i, j, val); DOK or dictionary of keys format: the hashmap you are thinking of; LIL or list of lists format: a list for each row and a list if pairs (j, val) in each list entry; CSR/CSC or compact sparse row/column: an array of indices where each row starts, an array of column indices and an array of values.

COO and DOK are great for changing sparsity structure; LIL is very useful if you have a lot of row-wise (or column-wise) operations, or need to manipulate rows regularly. CSR is great for matrix operations such as multiplication, addition etc. You use what suits your usecase, or change between formats (relatively cheap) as needed.

Comment: Re:hmmm (Score 1) 86 86

prohibit the private registration of domains which are "associated with commercial activities and which are used for online financial transactions

I'm not sure I have a big problem with this. If you do business with a company that can just disappear, that'd be a bummer. That said, you shouldn't do business with a company like that, but people aren't always smart.

I've registered several domains in the past and never been asked if they were for personal or commercial use. Are domain name registrars now going to be in the business of policing how domain names are used? At the present time, I don't think they have any involvement in how a domain is actually used, and many are used for multiple purposes, some commercial and some not. Who exactly is going to be responsible for doing this kind of content policing? If it is the registrars, I imagine the cost of registering a domain will go way up to cover their labor costs in monitoring content.

Comment: Re:Frosty (Score 1) 141 141

They would report to the parents, without notification to the student

Gotta call bullshit on this. It's illegal for a university to release that kind of information to anyone other than the student without their consent. Minors attending university have to do special paperwork to address this, but adult students have 100% control over information release to third parties.

That's actually not true. Specific information, such as grades, financial, and medical records are generally protected by laws in most states, and can't be released to parents without the student's consent, but I'm not aware of any such laws which cover other random information such as locations of WiFi access points that students have been using.

Comment: Re:IMAX sucks (Score 1) 190 190

For the first few times I saw IMAX it was good. Then IMAX decided to create just a large flat screen and slap IMAX logo to wring cash. The large flat screen is nowhere near the IMAX parabolic dome screen.

I think you're confusing IMAX and OMNIMAX. OMNIMAX has the dome shaped screen.

+ - Password storage service LastPass hacked.->

BitterOak writes: LastPass is a service which claims to securely store all your passwords in one safe place. According to this story, it proved not to be quite as safe as claimed. Apparently they were hacked. Hackers obtained people's e-mail addresses, password reminders, and encrypted versions of their master passwords. With these encrypted passwords, hackers could run brute force attacks to obtain weak passwords very easily. And the reminders may help them to figure out more secure passwords as well.
Link to Original Source

Comment: Re:Capitalist logic (Score 1) 389 389

If the DJ did indeed pay a fee to play said songs, then I don't see why another should be paid by the restaurant owner.

EXACTLY. What if the DJ had played the songs in a park? Would the city have to pay BMI's licensing shakedown fee?

If the owner of the park (the city government perhaps) were charging admission or otherwise benefiting commercially from the performance of the music, then yes they would have to pay the license fee.


How Facebook Is Eating the $140 Billion Hardware Market 89 89

mattydread23 writes: It started out as a controversial idea inside Facebook. In four short years, the Open Compute Project has turned the $141 billion data-center computer-hardware industry on its head. This is the comprehensive history of the project, including interviews with founder Jonathan Heiliger and members of the financial services industry who are already on board, plus a dismissal from Google's own data center guru Urs Holzle.

Comment: Re:a low-IQ child's IQ can be raised in some cases (Score 2) 185 185

I've had sat psychologist administered IQ tests a year apart and had my score differ by 10 points. I've been told that, in fact, this is perfectly normal and well within the accuracy expected of IQ tests by psychologists who take them seriously. I wouldn't worry about IQ scores changing (they may well do that, but it is equally likely measurement error). IQ is a very imperfect measure to begin with. Our ability to measure it, even under the best of conditions, is extremely poor. Take most IQ studies with a grain of salt.

You will have many recoverable tape errors.