Hello Brandon, Thank you for answering, I will take in account your suggestions when I will arrive to the third order shape functions part,
Kind regards, Jordi, On Monday, 30 December 2019 21:00:56 UTC-5, Brandon Gleeson wrote: > > Hi Jordi, > > > I took that course last year, and also had some troubles with the first > coding assignment. As Curro mentioned, there was an update to deal.ii after > the course was created that could affect the results for the 3rd order > solution. It had to do with a change in spacing of the quadrature points > from equidistant to Gauss-Lobatto for orders > 2. If you're also having > trouble with the 2nd order problem, that would suggest you have another > issue to sort out (looks like Jean-Paul gave you some feedback to help), > but I wanted to point you to this thread deeper within the Coursera forums > that helped me out in the end, as I was using a later release of deal.ii: > Coursera > Forum Link - Programming Assignment: Coding Assignment 1 > <https://www.coursera.org/learn/finite-element-method/programming/cUBqk/coding-assignment-1/discussions/threads/LMCIPik5EeiZ0w5m4xq4Gg> > > . > > The first assignment was by far the most difficult & time consuming, the > remaining ones got easier each time. I thought it was a great course and > learned a lot! > > Good Luck! > Brandon > > > > > <https://www.coursera.org/learn/finite-element-method/programming/cUBqk/coding-assignment-1/discussions/threads/LMCIPik5EeiZ0w5m4xq4Gg> > > > > On Monday, December 30, 2019, 3:31:18 AM MST, Curro Trigo < > [email protected] <javascript:>> wrote: > > > Hello Jordi: > > > > I also joined "The Finite Element Method for problems in physics" in > Coursera and I had similar problems. I worked them around by switching back > to version 8.2.1 of deal.II library. With version 8.5.0, the latest > available at that time, it did not work fine. I don’t know the root cause. > > > > I also think there is a mentoring problem with this particular course; a > new video should have been posted to clarify the changes required to make > the assignment work with the current versions of deal.II. > > > > Nevertheless I still think "The Finite Element Method for problems in > physics" in Coursera is highly recommendable. > > > > Best wishes for 2020. > > > > Curro Trigo > > On Sunday, December 29, 2019 at 10:29:11 PM UTC+1, Jean-Paul Pelteret > wrote: > > Dear Jordi, > > Firstly, welcome to the forum. Well, as this is a course assignment I > think that its fair to assume that some course mentor should be available > to guide you toward the solution to the problem. You say that you’ve had no > luck on the course site forum — that’s a bit poor. Anyway, I wouldn’t want > to give away the answer, but after skimming through your code and seeing > your comment that > > I checked my basis functions and its gradients and seem to be correct > > > I would say that you’re looking in the right sorts of places for the > problem. Remember that in the finite element method we use basis functions > to approximate the solution, and these need to evaluated in certain places > where we form approximations for certain calculations. You’ve seem to have > the “evaluated” part sorted, but what about the other part? What might need > to change when you move from linear to higher order shape functions in > order to ensure that those approximate calculations are performed > accurately? > > I hope that my somewhat cryptic response will give you a nudge in the > right direction. Oh, and I also hope that you take a look at our tutorial > programs sometime to see how we typically code up FEM problems. It’s good > to get a hand on the basics, but you might be pleased to know that the > deal.II library does most of this for you in a clean and easy to understand > manner. > > Best, > Jean-Paul > > On 28 Dec 2019, at 02:01, Jordi Parra Porcar <[email protected]> > wrote: > > Dear all, > > I am new to this group. I wanted to ask for some help as I am unable to > find the solution to a problem. > I am following a course in Coursera called "The Finite Element Method for > problems in physics". The course first assignment it is about coding with > dealii. > I have posted in the Coursera forum but got no answer so, I am trying by > here just to see if I am lucky and someone give me a hand. > The issue that I have is that I can only solve the problem with 1st order > basis functions as with quadratic and cubic basis functions it gives me an > error related with the K global matrix. > I have been going around discussions but still unable to find where is the > problem. I checked my basis functions and its gradients and seem to be > correct. > I uploaded all the files related to the problem. Now the ./main executes > the problem=1 with order=1, that is the linear basis function. > > Thank you all in advance and happy ending of the year! > > Jordi, > > -- > The deal.II project is located at http://www.dealii.org/ > For mailing list/forum options, see https://groups.google.com/d/ > forum/dealii?hl=en <https://groups.google.com/d/forum/dealii?hl=en> > --- > You received this message because you are subscribed to the Google Groups > "deal.II User Group" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to dea...@ googlegroups.com. > > To view this discussion on the web visit https://groups.google.com/d/ > msgid/dealii/5a12993f-9687- 4b5a-9ad5-e4711e49f6a4% 40googlegroups.com > <https://groups.google.com/d/msgid/dealii/5a12993f-9687-4b5a-9ad5-e4711e49f6a4%40googlegroups.com?utm_medium=email&utm_source=footer> > . > <CMakeCache.txt><CMakeLists. txt><FEM1.h><Makefile><cmake_ install.cmake> > <main1><main1.cc ><writeSolutions.h><_ b66323d90964cccb91c92f77bcb02a > b0_codingAssign1.pdf> > > > -- > The deal.II project is located at http://www.dealii.org/ > For mailing list/forum options, see > https://groups.google.com/d/forum/dealii?hl=en > --- > You received this message because you are subscribed to the Google Groups > "deal.II User Group" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected] <javascript:>. > To view this discussion on the web visit > > https://groups.google.com/d/msgid/dealii/47f96a24-8fa7-407e-9f96-2d151cc00de3%40googlegroups.com > > <https://groups.google.com/d/msgid/dealii/47f96a24-8fa7-407e-9f96-2d151cc00de3%40googlegroups.com?utm_medium=email&utm_source=footer> > . > -- The deal.II project is located at http://www.dealii.org/ For mailing list/forum options, see https://groups.google.com/d/forum/dealii?hl=en --- You received this message because you are subscribed to the Google Groups "deal.II User Group" group. 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