Possibility to output stuffs on the integration points?

[Chuyi Duan]

Dear all,

I'm using a struct to store informations on each integration point, by generating an output file I can only get a mean value of the points in a cell (.vtk file), it looks so "coarse" but it is actually not. So what I want to do is to output the stored stuffs on each points.
I've only found function attach_dof_handler(dof_handler_type) and attach_triangulation(triangulation_type). I'd like to ask if there is any possibility to creat a output file in that I can see how the integration points look like.

Best,
Chuyi

[Jean-Paul Pelteret]

Dear Chuyi,

No, as far as I am aware we have no specific function to help do this for you. However, there is an example in the code-gallery that shows how to write structure a VTK file and fill it with some data to be visualised at the quadrature points. You can modify and extend the code there to suit your needs.

Regards,

Jean-Paul

[Yi-Chung Chen]

Hi

I dont know if I understand your request correctly, but I guess you want to output vertices(Nodes) and its associated solution/result right?

If this is correct, then following might help you:

make sure you are using shared or general triangulation without refinement by deal.ii

if you are using general triangulation, then

const std::vector< Point<dim> > &vertices = triangulation.get_vertices();

then a for loop will do the trick to get coordinates of vertices and output/result vector at the same time. (all the vector can be actually looped though the same technique)

if you are using shared triangulation, then you might need to hack deal.ii (it is possible)

All best,

YC Chen

[Chuyi Duan]

Hi Jean-Paul,

thank you very much for you advice! I tried your code but i got in paraview only view of points (Gauss points) of them. Thats not what i want and I think i should combine stuffs  with triangulation. But it seems not possible to change Triangulation object when I try to refine it before output, maybe since i already called GridGenerator? Could you tell me how can i do something to modify Triangulation or DoFhandler object at the time of output? Thanks in advance.

Regards,
Chuyi

在 2017年7月14日星期五 UTC+2下午4:43:47，Jean-Paul Pelteret写道：

[Jean-Paul Pelteret]

Hi Chuyi,

I'm sorry but I don't understand your question. If its of any use, there's another thread thats related to this topic, namely where quadrature point data is being projected to the finite element support points and output as a continuous field. Is this what you're wanting to do?

https://groups.google.com/forum/#!topic/dealii/FW9Jy5_CUGY

Regards,

Jean-Paul