@StanShunpike oh it's a headache. I had a problem that ended up being six pages of algebra, I have a B average on the homework because the grader doesn't like my handwriting, and I'm not learning any useful theoretical things, just PDE solutions that would be quickly disposed of in mathematica.
You could LaTeX your solutions. My handwriting is atrocious, starting to LaTeX my solutions early on in undergrad was one of the best decisions I made.
Another benefit of typesetting is that it encourages prose. I can't tell you how frustrating grading as a TA was when the students handed in scribbled sheets with just equations on them and no explanation of their thought process or take on the problem.
and the parameters are given in the last few pages of the report too
except t = 100 and dt = ? ughh! if they got k = 0.25 and k = Ti/dt from the previous code that's k = 25/99 = 0.252525
that is the only combination that can produce it! but still the code is like >> erad(0.0075,0.0055,0.09,0.0001,0.25,100,99) Warning: Size input contains non-integer values. This will error in a future release. Use FLOOR to convert to integer values. > In erad at 6 Warning: Size input contains non-integer values. This will error in a future release. Use FLOOR to convert to integer values. > In erad at 18 Attempted to access sol(1.25253); index must be a positive integer or logical.
@usukidoll if I'm reading your thing right, your passing in Ti = 0.25 and dt=100, so that k, at the top of eradode, which should be the length, will be a float and less than one
@usukidoll notice that k=Ti/dt; and then they loop: for i=1:k, k is supposed to be the length of the vector of states, they use it to index into s,z, and r, setting values. It needs to be an integer
Just below Figure 10, they say k=0.25, but that refers to the k in the equation above, the magnitude of the inpulse at time tn. the k in eradode is an index for the state vectors
well, to fix your current problem, you could change line 21 from z1=sol(j+n+1) to z1=sol(j+n), but that is likely to introduce other errors down the way.
the problem is that you have a vector with 10001 elements and you are trying to access the 10002nd element, which doesn't exist
no, you need to make sure you don't go off the end of your vector. Someplace you have an inconsistency in your code. In one place you treat the sol vector as though it should have 10001 elements, and someplace else as though it should have 10002 elements. The real fix is to find out where the problem stems from and fix it there
I suspect you have an n+1 where you should have an n someplace earlier
I imagine the point of the exercise your working on is for you to develop some skills writing the code yourself, and debugging it when things go wrong, not necessarily just transcribing someone else's code
take this as a learning opportunity. Go back and put in a bunch of print statements all over the place and check to see what size sol is and what elements you are trying to access
or better yet, replicate the model from scratch with your own code
I wanted to do my own project really... on cat population but he was like no choose Insert name of paper here... the information is already there because lots of times student choose their own paper and it gets complicated
Sure, but I really doubt he wanted you to just transcribe and run their code. By trying to replicate their results you'll have something to check against.
I take fundamental issue with the model in that paper
They allow humans to kill zombies, which transitions them to R, but also allow the "dead" to rise, from R->Z.
now, I don't like the dead rising anyway, seems an old fashioned sort of zombie, but I particularly take issue with the fact that they don't distinguish between dead zombie and dead human
their dynamics has a single sink, namely Z
so their conclusion that zombies always win is a silly consequence of their model
for they literally don't allow any way for anything else to happen
@JoshuaLin because they can only change sites so fast, and it takes time, and we weren't lucky enough to be one of the first ones. I don't know when we will get it, but it might be a while longer.
What does chat think about this discussion? http://meta.physics.stackexchange.com/questions/5903/ It seems to me that @DavidZ may be demonstrating somewhat of an uncharacteristically trollish and intolerant attitude. A+ for passion, but you gotta keep things respectful bro! ;)
According to one of the answers to my post:
Physics.SE is not a homework help site, it is not meant to be a resource to teach people physics, and it is not a resource intended to help right conceptual misconceptions in students. When it was originally created, this site was meant to be a plac...
Rather than disallowing non-mainstream theories, I think the better approach would be to have a neon warning/caution banner at the top of non-mainstream posts. That would appease both sides, by allowing people to express their views even if they are perceived as non-mainstream (people are also free to downvote), while simultaneously helping to mitigate any perceived damage to the community that could result from promoting non mainstream ideas. Perhaps the flagging system could accommodate this?
@ACuriousMind Again, I appreciate the feedback. But your comments are somewhat insulting and what you describe is generally oppressive. I'm not aware of any other SE site that shares this mentality, for example if you go to SO and post a bunch of programming methodologies that go against mainstream best practices, proper discussion will ensue and people will explain why the ideas are wrong. I don't understand why Physics can't also support the same level of open forum.
@Giffyguy 99% of "non-mainstream" physics is nonsense. It's not like discussing alternative programming methodologies, it's like someone claiming all the computer scientists are wrong and that there is an algorithm that solves every problem in O(log log log n) or something.
Also, we are not a discussion forum, we are a site for questions which have definite answers
@ACuriousMind I can understand your fears here, and I disagree. If someone made such an absurd claim in SO it would probably get closed/removed. However, on SO it's a case-by-case basis, with no blanket topic prohibitions. I also hear you regarding the Q/A focus, however the problem here is that most of the interesting/frontier physics questions don't have definite answers in the way programming questions do. Most of frontier physics is still theory, after all.
@Giffyguy Mainstream physics questions that don't have definite answers are usually closed as too broad, too. We're not intended to be a site where we discuss newly developed physics, we're mostly there to clarify firmly established physics.
@ACuriousMind Ah, OK. Out of curiosity, how large do you think the non-mainstream physics society is? Do you see it a vast group of people, threatening to outnumber or overwhelm the mainstream physics society? Or do you view it as a relatively small and non-threatening fringe movement? I'm interested to hear your opinion on this, since I don't really know how people view this in general.
@Giffyguy I'm not under the impression that there is an organized "non-mainstream" society, the people doing it seem to be mostly isolated and lacking formal training in physics. Well, some older physicists also tend to write some weird stuff, but I don't think they're organized either. Non-mainstream physics is fringe, but very annoying fringe.
Is it possible to implement trackbacks from SE sites to the arXiv.org?
Example: Here is a list of trackbacks to the arXiv preprint arXiv:0905.2658 from various blogs. My feature-request is that if a future SE post mentions an arXiv number, say, arXiv:0905.2658, then a trackback is automatically...
According to one of the answers to my post:
Physics.SE is not a homework help site, it is not meant to be a resource to teach people physics, and it is not a resource intended to help right conceptual misconceptions in students. When it was originally created, this site was meant to be a plac...
