binary vtk files

Palabos General
#1

Hello,

this issue is not really related to Palabos, but maybe someone has an idea.
In order to save disk space I would like to write the simulation data as binary vtk file. Does anybody know the specifications for that? Or does anybody have a simple example code? In principle, it doesn’t need to be vtk. I just want to import the files in ParaView.
There is also a related question: Is there a data format readable by ParaView which can story data from more than one time step? If I have 5000 files of 5 MB each, it takes ages for the OS to access and copy the data. It would be much better to have only one or few large files containing many time steps. Is there a data format which can handle that?

Thanks a lot,
Timm

#2

Dear Timm

Tecplot data format is redable from para view 3.8

It is one of the strongest data format

I am using tacplot data format. It supports binary format, and you can store more than one time step in a single file

you can look to this refrence
http://download.tecplot.com/tecio/360/dataformat.pdf

also they have Pre-compiled library to read and write the data in their format.
http://download.tecplot.com/tecio/360/

I hope It will Help you.

Thanks
Saleh Bawazeer

#3

Hello SaS,

this seems to be very helpful.

Thank you very much!
Timm

#4

Hi Timm,

I can send you small VTK XML writer cpp code that you can use it - it does it in binary format. Let me know if you are still interested in it.

Cheers,
Alex

#5

Hey Alex,

yes, that would be nice. I just take all I can get and see which option is the best one for me.

Thanks,
Timm

#6

Hi Alex,

I’d be interested, too.

Could you just post the code here?

Best wishes,
Arne

#7

Hi guys,

Sorry for being late - was just really busy with everything. So here it is:


#include <vtkXMLStructuredGridWriter.h>
#include <vtkSmartPointer.h>
#include <vtkStructuredGrid.h>
#include <vtkIdList.h>
#include <vtkDoubleArray.h>
#include <vtkPointData.h>

void Solver::writeVTKWholePhase(std::string name)
{
    Solver::getWholePhase();
    if (rank==0)
    {
   		name=name+".vtk";
        std::ofstream fout(name.c_str());
        fout<<"# vtk DataFile Version 3.0\n";
        fout<<"Binary liquid phase field vtk representation\n";
        fout<<"ASCII\n\n";
        fout<<"DATASET STRUCTURED_GRID\n";
        fout<<"DIMENSIONS "<<NX<<" "<<NY<<" "<<NZ<<"\n";
        //fout<<"ORIGIN "<<floor(NX/2)<<" "<<floor(NY/2)<<" "<<floor(NZ/2)<<"\n";
        //fout<<"SPACING 1 1 1\n";
        fout<<"POINTS "<<NX*NY*NZ<<" double\n";
        for(int counterZ=0;counterZ<NZ;counterZ++)
            for(int counterY=0;counterY<NY;counterY++)
                for(int counterX=0;counterX<NX;counterX++)
                    fout<<counterX<<" "<<counterY<<" "<<counterZ<<"\n";
        fout<<"\n";
        fout<<"POINT_DATA "<<NX*NY*NZ<<"\n";
        fout<<"SCALARS phase double\n";
        fout<<"LOOKUP_TABLE phase_table\n";
        for(int counterZ=0;counterZ<NZ;counterZ++)
            for(int counterY=0;counterY<NY;counterY++)
                for(int counterX=0;counterX<NX;counterX++)
                    fout<<phase[counterZ*NX*NY+counterY*NX+counterX]<<"\n";

    }
}

void Solver::writeWholePhase(std::string name)
{
    Solver::getWholePhase();
    if (rank==0)
    {
        name=name+".vts";

        vtkSmartPointer<vtkPoints> points = vtkSmartPointer<vtkPoints>::New();

        for(int counterZ=0;counterZ<NZ;counterZ++)
            for(int counterY=0;counterY<NY;counterY++)
                for(int counterX=0;counterX<NX;counterX++)
                    points->InsertNextPoint(counterX,counterY,counterZ);


        vtkSmartPointer<vtkDoubleArray> data = vtkSmartPointer<vtkDoubleArray>::New();
        data->SetNumberOfComponents(1);
        data->SetName("Phase");



        for(vtkIdType i = 0; i < points->GetNumberOfPoints(); i++)
        {
            double * temp_data=&phase[i];
            data->InsertNextTupleValue(temp_data);
        }

        vtkSmartPointer<vtkStructuredGrid> structuredGrid = vtkSmartPointer<vtkStructuredGrid>::New();
        structuredGrid->SetDimensions(NX,NY,NZ);
        structuredGrid->SetPoints(points);
        structuredGrid->GetPointData()->AddArray(data);

        vtkSmartPointer<vtkXMLStructuredGridWriter> writer = vtkSmartPointer<vtkXMLStructuredGridWriter>::New();
        writer->SetFileName(name.c_str());
        //writer.SetPoints();
        writer->SetInput(structuredGrid);
        writer->Write();
    }
}