Re: [Getfem-commits] please merge branch devel-tetsuo-xml

[Tetsuo Koyama]

Dear Kostas

Thank you very much for taking the time to review.

> I think it is an important contribution to add vtu support, especially if it 
> is binary/compressed, just ascii is not very useful.
Thanks. I agree that binary/compressed is important. After this change
is confirmed, I would like to add that option.

> However we might need to discuss a bit on how to do it. As far as I can see 
> you have used boost for xml writing. I think we
> had dropped our dependency on boost and I am not very keen on reintroducing a 
> dependency on boost.
I agree with the policy that projects don't use boost. In the end, I
made changes to eliminate the dependence on boost in the end. If there
is any remaining dependence, please point out . I am sorry that the
commit is complicated. The current vtu object does not require
dependency to boost even if when extending to binaries.

>Before we merge this, I would like to hear some arguments for one solution or 
>another. The first thing to check is what others do.
> How is vtu export implemented in other software like e.g. fenics? What is the 
> more future-proof way of implementing vtu support?
I didn't search fenics but meshio package (This is a major package
which is used to convert mesh format. You can install by `apt install
python3-meshio`) and mayavi2.
Both are built by full scratches of writing text and binary like
getfem project is doing. They reffer vtk file format pdf.
https://vtk.org/wp-content/uploads/2015/04/file-formats.pdf

> What is a solution with least dependencies? If we have to depend on an 
> external library it might be better to depend
> on vtk directly https://www.paraview.org/Wiki/VTK/Examples/Cxx/IO/WriteVTU
That is a good point. It maybe a good idea of using library, but we
have to use cmake to link vtk librayr. I think it is difficult to use
with getfem using automake. (Is there any plan to use cmake in
getfem?)

This is hello world of vtk library.
https://lorensen.github.io/VTKExamples/site/Cxx/GeometricObjects/CylinderExample/

> Have you done some research regarding these questions?
That is all. If I need I search of fenics I will do it !

> There is also another thing that I would like to ask you about. Could you 
> please don't use markup in your git commit description? It might look nice in 
> your git client but it looks ugly and difficult to read on other's systems.
Thank you for pointing it out. I used emoji prefix which is popular in
my local. It is not good to use it in a global community. Sorry.

> just to add that for compressed vtu files I use the attached conversion 
> script based on binary vtk files exported from getfem.
Thanks. I'll use it.

Thank you for reading.

BR Tetsuo

2020年5月7日(木) 19:21 Konstantinos Poulios <address@hidden>:
>
> just to add that for compressed vtu files I use the attached conversion 
> script based on binary vtk files exported from getfem.
>
> On Thu, May 7, 2020 at 11:59 AM Konstantinos Poulios <address@hidden> wrote:
>>
>> Dear Tetsuo
>>
>> I think it is an important contribution to add vtu support, especially if it 
>> is binary/compressed, just ascii is not very useful. However we might need 
>> to discuss a bit on how to do it. As far as I can see you have used boost 
>> for xml writing. I think we had dropped our dependency on boost and I am not 
>> very keen on reintroducing a dependency on boost.
>>
>> Before we merge this, I would like to hear some arguments for one solution 
>> or another. The first thing to check is what others do. How is vtu export 
>> implemented in other software like e.g. fenics? What is the more 
>> future-proof way of implementing vtu support? What is a solution with least 
>> dependencies? If we have to depend on an external library it might be better 
>> to depend on vtk directly 
>> https://www.paraview.org/Wiki/VTK/Examples/Cxx/IO/WriteVTU
>>
>> Have you done some research regarding these questions?
>>
>> There is also another thing that I would like to ask you about. Could you 
>> please don't use markup in your git commit description? It might look nice 
>> in your git client but it looks ugly and difficult to read on other's 
>> systems.
>>
>> Best regards
>> Kostas
>>
>>
>>
>>
>> On Thu, May 7, 2020 at 2:07 AM Tetsuo Koyama <address@hidden> wrote:
>>>
>>> Dear getfem project
>>>
>>> Could you merge devel-tetsuo-xml?
>>> This branch is addition of vtu_export class.
>>> By using this class we can export xml unstructured grid format vtk
>>> (only ascii format and write_point_data).
>>> I tested it by using meshio package (https://github.com/nschloe/meshio).
>>> In the future, the binary format and write_cell_data method may be extended.
>>>
>>> Thank you for reading.
>>>
>>> BR Tetsuo
>>>