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Comment Re:Is FORTRAN still winning? Was Re:Poor Alan Kay (Score 1) 200 200

Repeatedly allocating and deallocating can give a huge performance hit, so I tend to do all my allocations before the main loop.

which is the correct way of doing it. Allocating and deallocating, especially larger chunks of memory, requires you to interact with the operating system.
This should off course be avoided in tight loops.

Comment Re:Is FORTRAN still winning? Was Re:Poor Alan Kay (Score 1) 200 200

I've been writing a scientific simulation in Fortran for half a year now. I usually like to write in some combination of C and Python.

While Fortran does make the life of a compiler writer easier, I think C benefits from being a small and very popular language.
C compilers are just more advanced, which gives it the speed advantage. But the speed difference for most purposes is negligible.
Choosing the right algorithm and approximations is a much more important concern (factors of 10-100-1000 vs. 1.1-1.2-1.3).
Dynamic memory management is not much different from C.

In my experience, Fortran is extremely useful for expressing linear algebra, which is heavily used in quantum mechanics.
At least it is much much better than C. So in terms of programmer efficiency in scientific calculations, I think Fortran beats C by quite a margin.

Fortran sucks at pretty much anything else though. For example, I think it's a lot easier to have a config module (e.g. class) to manage simulation parameters and recompile the whole application every time you change settings than it is to use an actual configuration file.

The next time I write a scientific application, I think I will have Python handle the logistics (parallelization, files, user input, etc.) and let Fortran do the (heavy) computations.

Comment Re:Has anyone done this? (Score 1) 234 234

I didn't but one of my friends did. He is some 15 years older than me, and was working as an electrician. On top of that, he is dyslexic.
We both study physics now. He's soon finished with his masters degree. I started right after high school, and I'm currently doing a phd.

Comment RE: howto (Score 1) 234 234

I am a phd student in physics. I started the same year as an electrician about your age. I'm not sure if he quit his job or went down in time.
But he manages very well.

He's only a few years behind me, and about to finish his masters degree. He's even dyslexic, so I'm quite impressed by him.

Submission + - Dice Holdings has written off Slashdot Media at the close of 2013-> 3 3

moogla writes: Apparently Dice.com could not make Slashdot work they way they wanted to; with a murky plan to tap into the Slashdot-reader community to somehow drive attention or insight into other Dice Holdings properities, they've burned through

$7.2 million of intangible assets and $6.3 million of goodwill related to Slashdot Media

and have only started to realize some improvement on related sites. With ad revenue declining and not expected to pick up (read: everyone who uses Slashdot uses adblocking softwarwe), it appears that the Slashdot stewardship experiment by Dice Holdings has been a financial failure. Since the site has been redesigned in a user-hostile fashion with a very generic styling, this reader surmises Dice Holdings is looking to transform or transfer the brand into a generic Web 3.0 technology property. The name may be more valuable than the user community (since we drive no revenue nor particularly use Dice.com's services).
Link to Original Source

Submission + - Ask Slashdot: Can some of us get together and rebuild this community? 21 21

wbr1 writes: It seems abundantly clear now that Dice and the SlashBeta designers do not care one whit about the community here. They do not care about rolling in crapware into sourceforge installers. In short, the only thing that talks to them is money and stupid ideas.

Granted, it takes cash to run sites like these, but they were fine before. The question is, do some of you here want to band together, get whatever is available of slashcode and rebuild this community somewhere else? We can try to make it as it once was, a haven of geeky knowledge and frosty piss, delivered free of charge in a clean community moderated format.

Submission + - Alternatives to Slashdot post beta? 8 8

An anonymous reader writes: Like many Slashdotters, I intend to stop visiting Slashdot after the beta changeover. After years of steady decline in the quality of discussions here, the beta will be the last straw. What sites alternative to Slashdot have others found? The best I have found has been arstechnica.com, but it has been a while since I've looked for tech discussion sites.

Submission + - Slashdot forces a beta site by default

kelk1 writes: As a poor submitter found out (https://developers.slashdot.org/story/14/02/05/2328224/html5-app-for-panasonic-tvs-rejected---jquery-is-a-hack), Slashdot (https://slashdot.org) suddenly forced a preview of its beta site without any warning on all its viewers.

Judging by the comments, the feedback was immediate and clearly negative.

I cannot speak for the forum moderation side, but my reaction to the front page was an knee jerk: "Oh no!, not another portal full of noise I cannot speed-read through." Text and hyperlinks are what we need, please, and as little graphics as possible. Think lynx, thank you.

Submission + - Richard Nixon Announces His Approval For Slashdot Beta 3 3

MightyMartian writes: Former US president (and everyone's favorite funny man) Richard M. Nixon announced his approval of the Slashdot Beta site.

"I was just telling Pat this morning as I made sweet Nixon love to her that what the web needed was a whitespace-riddled atrocity. Slashdot Beta is the Tet Offensive of discussion sites, so screw you, you stupid hippies."

Henry Kissinger was said to have been very pleased as well. Dr. Kissinger was quoted as saying "In Soviet Russia, Slashdot betas you!"

Comment Re:Space/time duration/distance (Score 3, Interesting) 81 81

Seven billion light years away (seven billion years ago)

I may not have this right, but due to the expansion of space, wouldn't it have been closer than seven billion light years away at the time of the kaboom? And if the light's taken seven billion light years to get here, space will have expanded further, so the remnants would now be further than seven billion light years away. Right?

Or is this the sort of thing where you can be specific about the distance, or the time, but not both?

Wikipedia has an answer, but I think the above is just meant to give the layman some rough understanding of what's going on.

Beware that it is extremely difficult to measure these kinds of distances exactly. The figure may be a few orders of magnitude wrong, so whether you take into account the expanding universe or not may not be that important...
Cosmologists measure everything in gigaparsec. 7b light years is only 0.3 GPc so it may not be that important.

"It's what you learn after you know it all that counts." -- John Wooden

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