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Comment: Re:Is FORTRAN still winning? Was Re:Poor Alan Kay (Score 1) 192

by Rising Ape (#48895443) Attached to: Bjarne Stroustrup Awarded 2015 Dahl-Nygaard Prize

Maybe according to the strict F95 standard it's not allowed, but I've done it. I think it was officially introduced in F2003 (or some TR that I forget) but compilers supported it even before then. Similarly for allocatable dummy arguments to subroutines.

Not to say there aren't some weird quirks with Fortran arrays, like how if you pass an allocatable array to a subroutine where the dummy argument is not allocatable then it *must* be allocated, even if the subroutine isn't going to touch it.

Comment: Re:Is FORTRAN still winning? Was Re:Poor Alan Kay (Score 1) 192

by Rising Ape (#48895371) Attached to: Bjarne Stroustrup Awarded 2015 Dahl-Nygaard Prize

It's a hardware thing -- the memory bus and memory read/write speeds are still a limiting factors, particularly as CPU cores get faster and more efficient.

Oh yes, I've seen plenty of code that's limited by memory bandwidth. But I don't think that's what's going on here - simply deallocating and reallocating shouldn't actually touch all of the memory in question, should it?

Fortunately for that kind of code, avoiding such reallocations isn't difficult.

Comment: Re:Is FORTRAN still winning? Was Re:Poor Alan Kay (Score 2) 192

by Rising Ape (#48895109) Attached to: Bjarne Stroustrup Awarded 2015 Dahl-Nygaard Prize

Does it still win with dynamic memory allocation? How granular is the dynamic memory allocation? Complete like C?

Fortran's dynamic memory allocation is much easier to work with than C's. You simply declare a variable allocatable, then allocate as needed with the appropriate size. It automatically gets deallocated when it falls out of scope, so no memory leaks (at least since F95).

e.g.

real, allocatable :: myarray(:)

allocate (myarray(1000), stat=ierr)
(something to check error code ierr here)

I've written a bit of finite difference code in Fortran. Repeatedly allocating and deallocating can give a huge performance hit, so I tend to do all my allocations before the main loop. Not entirely sure why the penalty is so big, but it seems to be - these are allocations of hundreds of MB or even a few GB, so the cost of operations done on the arrays should dwarf the cost of the allocation. Unless there's some underlying reason why touching newly allocated memory is so slow, but I don't know enough about how virtual memory behaves to say.

Comment: Re:The future of the internet, really (Score 1) 159

by Rising Ape (#48783565) Attached to: Inside North Korea's Naenara Browser

If end user hardware doesn't support it or isn't configured properly, then they will be completely unaware of and unaffected by its existence.

End user hardware generally does support it though - any vaguely modern computer, smartphone or tablet should automatically pick up and use an IPv6 address if available. So if the ISPs start supplying v6 it's essential that it works reliably, because the users' devices will try and use it. Broken v6 does affect connectivity, even if v4 still works fine. And even if the fault is with the users own equipment, you can bet they'll be complaining to the ISP.

Second post because I realised my first one doesn't directly address your point above.

Comment: Re:The future of the internet, really (Score 1) 159

by Rising Ape (#48783175) Attached to: Inside North Korea's Naenara Browser

That should be true in theory, but the IPv6 hardware & software is nowhere near as well tested as the IPv4 equivalent, both in terms of home equipment and in the ISPs own networks. How often does this kind of thing work perfectly first time? And the staff don't have the same experience with it to fix problems when they do occur. Anything new is a risk, and since hardly any home customers are demanding IPv6 it might seem like it's a risk not worth taking until made absolutely necessary by v4 exhaustion.

That's not what *I* want, but from an ISP's perspective I can see how it would make sense to prepare & test their network for v6 steadily, slowly and thoroughly but not actually deploy it while they still have enough v4 addresses.

Comment: Re:The future of the internet, really (Score 1) 159

by Rising Ape (#48781369) Attached to: Inside North Korea's Naenara Browser

I assume that's for the US, which seems ahead of the game despite having plenty of v4 addresses.

Here in the UK, none of the major ISPs have deployed v6 at all, and I don't think any of the mobile companies have either. I suppose they're just risk averse, as dealing with support calls for unexpected problems isn't cheap and their margins aren't huge.

Comment: Re:Quebec Language Police (Score 1) 578

by Rising Ape (#48726571) Attached to: What Language Will the World Speak In 2115?

So you could argue: they are neither english nor french as both languages adopted them from the same source. But that is incorrect in so far as english indeed adopted the words via the french invaders and not via the latin/roman invaders.

Those words in the original post were adopted into English long after Anglo-Norman was dead, so invasion can't be the answer here. They aren't native French words either - both English and French for some reason seem to like to coin new words from the classical languages. I suppose they thought telephone and television sounded grander than farspeaker and farseer (though we do have loudspeaker, oddly). This tendency seems to have greatly reduced recently though - computing terms are generally made from words already in English rather than new borrowings.

I don't think the original poster claimed that French had borrowed them from English, just that they are not native French.

Comment: Re:my rant... (Score 1) 323

by Rising Ape (#48145621) Attached to: How English Beat German As the Language of Science

Yes that's right, but the Norman words are so well integrated now that most English speakers wouldn't recognise them as foreign. The German ones still tend to look German. I doubt too many people would see this post and know that recognise, foreign, tend, recent, doubt, people and post are loanwords. "Integrate" still has a foreign feel about it though.

Comment: Re:BBC content paid for by Brits (Score 1) 363

by Rising Ape (#47869367) Attached to: BBC: ISPs Should Assume VPN Users Are Pirates

Prescription drug prices in the US market are much higher than the NHS negotiated prices; without the US market and the high amount of US consumer spending on drugs, drug companies would have little incentive to invest in new drugs.

Your own doctors' and hospitals' inability to negotiate a good deal isn't the NHS's fault. You don't really think that if the NHS paid more the drug companies would say "oh well, we'll charge everyone else less", do you? They'll charge as much as they can get away with, just like now.

A more likely reason for drugs being so expensive in the USA is that they spend more on sales & marketing than R&D. How much cheaper would it be if they didn't do that? Don't blame your own dysfunctional system on the NHS "not paying up" because they do, and the companies make a fat profit out of it.

Comment: Re:BBC content paid for by Brits (Score 1) 363

by Rising Ape (#47864097) Attached to: BBC: ISPs Should Assume VPN Users Are Pirates

For example, American consumers and taxpayers are paying for most of the medical research that the UK's single payer system would never be able to finance on its own;

What? The NHS pays for is medicines and technology at prices negotiated with the pharmaceutical companies. It doesn't get them for free.

Comment: Re:Reprocessing? (Score 1) 258

by Rising Ape (#47802531) Attached to: Feds Want Nuclear Waste Train, But Don't Know Where It Would Go

The fact that material with less than 2% fissile content can't go critical on fast neutrons is easily calculated by looking at the well measured fission and absorption cross-sections for U-238, U-235 and Pu-239. There's a *reason* why fast reactors use fuel with fissile content of 15%-20%, despite the higher cost of doing so.

Everything that happened at Fukushima can be explained by loss of AC power -> loss of coolant -> decay heat driven meltdown -> containment failure due to containment pressure & temperature beyond design limits. The decay heat is quite large - tens of megawatts for hours to days after shutdown. There's absolutely no need to invoke criticality to explain what happened, and absolutely no evidence that there was any such criticality. And a detector at the gate certainly couldn't provide any such evidence as the cores were and are inside enough shielding to block the neutrons that result from full power operation. You know, to stop the workers from getting radiation poisoning from normal operations. Any neutron pulse large enough to be detected there would have had to come from a fission reaction large enough to pretty much level the entire site and kill everyone nearby.

And before you mention the spent fuel pools again, the fuel in those has been inspected and found to be intact. So no meltdown there.

The weird thing is that my original post was explaining why a particular nuclear solution *wasn't* a quick and easy answer. I'd have thought that'd be the kind of thing you'd agree with.

If I were a grave-digger or even a hangman, there are some people I could work for with a great deal of enjoyment. -- Douglas Jerrold

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