Re: [deal.II] what is the different between VectorTools::point_value and fe_values.get_function_values()?

2019-03-19 Thread Wolfgang Bangerth
> I think that with the H curl conforming element like FeNedelec or > FeNedelecSZ, > my solution vector has continuous tangential component, isn't it? Yes. > Thus, Is there some where I can see my vector solution is discontinuous? Can > I > check it by visualization? Yes, you can do

Re: [deal.II] what is the different between VectorTools::point_value and fe_values.get_function_values()?

2019-03-18 Thread Phạm Ngọc Kiên
Thank you very much for your guidance. I think that with the H curl conforming element like FeNedelec or FeNedelecSZ, my solution vector has continuous tangential component, isn't it? Thus, Is there some where I can see my vector solution is discontinuous? Can I check it by visualization? I think

Re: [deal.II] what is the different between VectorTools::point_value and fe_values.get_function_values()?

2019-03-18 Thread Wolfgang Bangerth
On 3/18/19 4:14 AM, Daniel Arndt wrote: > > VectorTools::point_value() does more or less the same you are doing above > manually, i.e. calling GridTools::find_active_cell_around_point() and then > initializing a FEValues object for evaluating the given finite element > vector. Specifically,

Re: [deal.II] what is the different between VectorTools::point_value and fe_values.get_function_values()?

2019-03-18 Thread Daniel Arndt
> > [...] > 1. When evaluating point is on the vertex of a cell, this means that there > should be several cells in 3D have this vertex. > Thus, my first question is the function : > > const std::pair::active_cell_iterator, Point> > cell_point =

Re: [deal.II] what is the different between VectorTools::point_value and fe_values.get_function_values()?

2019-03-14 Thread Phạm Ngọc Kiên
I highly appreciate all of your answers. It becomes clearly for me to look through the library. Let me show all of my function and my ideas below. I set the point for evaluating its solution to be on the vertex of a cell, and using the following function to get the solution template void

Re: [deal.II] what is the different between VectorTools::point_value and fe_values.get_function_values()?

2019-03-14 Thread Wolfgang Bangerth
On 3/14/19 1:28 AM, Phạm Ngọc Kiên wrote: > > So for the first function > VectorTools::point_value(dof_handler,solution,point,values); > I can specify the observed point in real coordiante, solution vector and > dof_handler to get the values, right? Correct. > For the second one, assuming

Re: [deal.II] what is the different between VectorTools::point_value and fe_values.get_function_values()?

2019-03-14 Thread Jean-Paul Pelteret
Dear Pham, When you use the FEValuesExtractors in conjunction with the FEValues class using the operator[] like you’ve done here > fe_values[vector_re] then what is returned is an FEValuesViews type object. Since your vector_re extractor is of type FEValuesExtractors::vector, the returned

Re: [deal.II] what is the different between VectorTools::point_value and fe_values.get_function_values()?

2019-03-14 Thread Phạm Ngọc Kiên
Thank you very much for your answer. So for the first function VectorTools::point_value(dof_handler,solution,point,values); I can specify the observed point in real coordiante, solution vector and dof_handler to get the values, right? For the second one, assuming that I am using QGauss for

Re: [deal.II] what is the different between VectorTools::point_value and fe_values.get_function_values()?

2019-03-14 Thread Phạm Ngọc Kiên
Thank you very much for your answer. So for the first function VectorTools::point_value(dof_handler,solution,point,values); I can specify the observed point in real coordiante, solution vector and dof_handler to get the values right? For the second one, assuming that I am using QGauss for

Re: [deal.II] what is the different between VectorTools::point_value and fe_values.get_function_values()?

2019-03-13 Thread Wolfgang Bangerth
On 3/13/19 8:21 PM, Phạm Ngọc Kiên wrote: > I am testing my codes for output the solution at a point in my numerical > model. > I saw in the library 2 ways to do this task. The first one is to use > VectorTools::point_value() function and the second one is > fe_values.get_function_values().