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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: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.

Comment: Re:Slashdot you are no better (Score 1) 474 474

Oh just you wait, it will eventually be subjected to the slow burial. I guess I should not have said 'censored' since .. well the editors weren't actually removing content right? They were instead being extremely selective in which articles got through and how that would affect the context of the story. What SF does is not right; it's contrary to the entire purpose of the site. The chinese blocked it ages ago. Maybe their great firewall deserves more credit than we give it /sarcasm

Comment: Slashdot you are no better (Score 3, Informative) 474 474

I have been around here a long time.

I can honestly say that I am dissapointed to see /. post gloating over a row brewing on another community site while at the same time censoring discussion and posts related to the recent and ongoing Sourceforge controversy. Choosing which subs stay and which go is going to upset a small but vocal set of users. They would be stupid not to know this.

In the case of Sourceforge, I think it's much worse to sell out and betry the trust of an entire community. But let's not talk about it!

Comment: This is just in time to be bypassed entirely (Score 0) 179 179 the also-announced plans for wireless charging and docking. (okay sorta)

It'll be a while before the wireless docking and charging can replace wired connections, BUT, I think it's soon enough that this situation may somewhat resemble the slow uptake of Blu-Ray over DVD due to streaming becoming feasible.

Comment: Re:Either of the poles woulc cause this effect (Score 1) 496 496

If you start a mile north of the South Pole, walk a mile south, then you cannot walk west, so it still fails.

Also, the North Pole isn't ice-free all year long. (I've not been keeping up with how much (if it has happened yet) it is ice-free during a year, but it's certainly not the whole year. Yet.)

Comment: Re:The Road Warrior (Score 1) 776 776

...not a sequel, but a cash-in remake.
It's not a Mad Max movie. The main character isn't Max, the atmosphere isn't Mad Max's, it just happened to have spiked cars chasing plated cars in the wastland.

Indeed. What they should have done was get the writer/director of the original film, who I gather had been trying to get a sequel made for over a decade, to come and write and direct the new one. Clearly whoever they got to write this didn't really understand Max's character at all.</sarcasm>

The sooner you fall behind, the more time you have to catch up.