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short_circut

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" Imagine if eating the wrong thing wrecked your insides, but eating the right thing only gave you tremendous pain, cramping, and poops."

Not only do the things that you mention do that, but also things like salads :(. Trying to lose weight with IBS can be a PITA

I don't disagree. Fortran is brilliant at what it does.... but I find many of its object oriented features to be very obtuse compared to C and C++. The way it uses pointers drives me insane. Building certain datastructures in fortran just takes too much time.

I kind of wish I could find a good way to make Fortran and C play nicely together. (There are some compiler dependent peculiarities that I have encountered that make it difficult.)

Fortran's intrisics and file handling capabilities make it indispensable in the work I do.... So it is really a love hate relationship.

"In times where compilers are smart enough to basically rewrite and change code for performance reasons it is completely inexcusable that the order of source arguments to process is still that relevant."

After reading the comments on C and the difficulties the author had in the compilation process.... All I can say is Garbage in garbage out. I have worked in the HPC enviornment for a number of years using both Fortrash and C. The errors the author encountered would have been avoided by someone with any experience developing large softwares. I learned these things after working on my first project and now they barely, if at all, factor into my development time. Make sure you build and keep a dependency graph while you are developing and this becomes a non issue.

I find the requirement for an active Github account to be questionable. 99% of the code I write is owned my someone else. I do after all work for a living. I wonder how true this is of many other people too. If I am writing code at home then I am probably not spending much time to make it look nice. I don't have time to write it at home much less make it look good to a recruiter.

After reading the solution presented, what strikes me is that there is very little new math in it. Before you jump down my throat let me explain as this is quite an impressive effort.

Equation 7 bears a striking resemblance to what you would get if you started with a Liouville vonNeumann equation and tried to solve it in time. Infact all of the equations seem to follow this path.

See for example the books: 1) Charge and energy transfer dynamics in Molecular systems by Volkhard May and Oliver Kuhn (chapter 2)

2) Chemical Dynamics in Condensed Phases by Abraham NItzan.

I find it a bit surprising to not see these in the reference material. Everything in this paper screams Liouville von-Neuman equation.

Honestly I feel like this is an even bigger problem in the natural sciences. In my experience journals want strong and interesting positive results. They rarely want negative results unless it is debunking a previous result that seemed interesting and positive. I have worked on projects before, that while interesting and on a solid theoretical base as far as approximations go, were ultimately incorrect for what ever reason. I should be able to publish and report on this so no one else wastes their time on it or can find a glaring flaw in it and build upon it. While the initial idea may be a good one the implementation of that idea is not always a good one. It can be useful to other scientists to know these things.

I agree with you in as far as it makes a great multiplayer element. In the vs the computer game it is a bit of a crapshoot though. Working with different world leaders is not something that is possible. You can't sit there and strategize over several votes. Futhermore the later in the game you are the more frequently they meet. By the information era they are meeting every 10 turns.

It is interesting to hear them talk about the game getting complex. I think in the latest version they hit that wall with the world government. It is probably one of the most unfun and distracting features that Civ games have gotten.

I do think they can add more complexity in other areas hough.

Unfortunately there are several stories floating around where the law abiding gun owner was at the far end of the house and had enough time to get a gun out and fire through the door at the calamity coming forth. Which has frequently lead to the death and/or life time conviction of said law abiding gun owner. This might be ok if it weren't for the frequency with which these law abiding gun owners had their homes mistakenly raided.

You are probably one of the few. But I wouldn't buy too much into the argument that their rates have to go up. Internet speeds are higher and congestion are lower in many other countries where their rates are cheaper. I think there is one reason and one reason alone for this. That reason is localized monopolies. Take a quick gander into the deals the ISPs cut with local government. Prepare to be disturbed.

I am almost certain it wasn't included for some reason like that. I also suspect that they were using an outmoded version of fortran. Clicking the extra links would tend to validate that suspicion.

Also performance of fortran code is quite dependent on the compiler and compiler options. Somethng that was not well described.

The xml files can be huge, but wavefunction files in general tend to be. The main point being that it allows for direct access to the files for custom code work.

I can quantify a little slow with a specific research experience. This isn't the case for all uses of Quantum Espresso, etc....

When I run an HSE or PBE0 calculation on 192 atoms it takes just over 2 weeks of computation time using quantum espresso. When my co-worker did it in vasp using the same computing systems it took just a couple of days. I don't really know the reason for this.

From time to time things like this creep up.

One of the quirks you should be aware of an enforce in all runs where this is relevant is you need to set

wf_collect=.true.

if you do not then each subsequent run will require the same number of processors in the same configuration each time the program is run.

http://www.quantum-espresso.org/wp-content/uploads/Doc/INPUT...

I actually use Quantum Espresso rather extensively in my own research. It should work quite well with an interface like this. It has a sub-program pp.x specifically designed to make common plots out of the programs output.

I can tell you that it tends to be a little slow compared to some other codes such as VASP, and it does tend to take up a good deal more disk space. It has a few other quirks but it is a great program. Also its wavefunctions can be exported to XML files.

If you are looking anytime soon for people with computational physics/chemistry specific knowledge I may be looking for work soon.

I remember when something like this was being done during the manhunt for the boston bombers. It was pretty exciting the rate at which updates were coming. THere were people in the stream who lived there live updating things. It is amazing how fast information travels these days. In a matter of seconds hundreds of people knew exactly what was going on. This is a rather exciting development as far as documenting world events goes.

I wonder how much patent licencing adds to the cost. The author mentioned how wonderful of an idea this bimetallic strip was, but that means someone invented it and someone probably holds a patent on it. How much does it cost to use that innovation?

Low pass filters are absolute miracles when working with numerical derivatives. I have had instances where that was the only reason I ever got anything meaningful out of them. It really comes down to the fact that the numerical representation of a function is in general not truly analytic. It is has kinks and bends all over the place.

For me I was always reassured by everyone who mattered to me that with a degree in physics I could go just about anywhere because my analytically skills would open doors. Hearing that day in and day out breed in a sense of brainwashedness. Perhaps I am the one who is wrong. I certainly hope so.

I am currently about a year away from my PhD in computational physics and chemistry and looking out towards the future I have very similar sentiments to this professor. Finding a decent job in academia is very very difficult. Even when you do get one it really won't be worth the work and time you have to put into it. At least in my field it is much better to develop your skills elsewhere and use that to enter into industry. I just wish someone had told me this 4 years ago.

Given the skill level and investment required to get a competitive STEM degree and the amount of profits a STEM person can produce for a company's long term profits I think that they are actually potentially underpaid.

I frequently ask myself that same question. I wish I had an answer for you. I could attempt to answer it but the NSA would probably put me on a no fly list or something as a limited form of extrajudicial punishment. Or maybe I am paranoid. But then again given all the things I have learned about what the US has done how can I not be?

This is why laws need change logs for when they are modified. I knows bills have something of the sort, but they are hard to follow. Anyone who finds a specific set of laws relevant can subscribe to them and get an email when the law is changed.