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problems with compiling self defined class

Hi at all,

i tried to implement my own class(class Tracing) which follows the flameFront and writes the current position of the flame to a file.
So i wrote two files:

Tracing.H
Tracing.C

After including flameTrace.H in my solver and creating an Object of this class by
...
Tracing flameTip;
...
and using the two methods for following the flame and write the position to the file, by:

flameTip.follow();
...
flameTip.write();

I allways get this error message while compiling the solver:

Make/linux64GccDPOpt/reactingTotalFoamFE2.o: In function `main':
reactingTotalFoamFE2.C:(.text+0x338f): undefined reference to `main::Tracing::Tracing()'
reactingTotalFoamFE2.C:(.text+0x9bdf): undefined reference to `main::Tracing::~Tracing()'
reactingTotalFoamFE2.C:(.text+0xa74b): undefined reference to `main::Tracing::follow()'
reactingTotalFoamFE2.C:(.text+0xa79e): undefined reference to `main::Tracing::writeToFile()'
reactingTotalFoamFE2.C:(.text+0xdb2a): undefined reference to `main::Tracing::~Tracing()'
collect2: ld returned 1 exit status
make: *** [/nfs/home/fleischer/OpenFOAM/fleischer-1.6.x/applications/bin/linux64GccDPOpt/reactingTotalFoamFE2] Error 1

I don't know what "undefined reference to main::Tracing::....." shoud mean!?:confused:

Can anybody help me please!

Thanks a lot in advance!

Victor

That seems odd. Have you changed Make/options and/or Make/files as well? Is this part of a library or are you compiling it with the solver?

And are you sure you meant flameTrace.H instead of Tracing.H:

Quote:

After including flameTrace.H in my solver and creating an Object of this class by

Thank you l_r_mcglashan, I think there are different problems but the basic one is that i didn't know that i need a make-folder for compiling the header file correctly.
I think i will try the whole thing in a easier way....but thanks a lot for your help!

Grabbing an example from the sources, have a look at the application heatTransfer/chtMultiRegionFoam. See how the regionProperties class is used.

Thank you, the regionProperties helps a lot. The problem I have at the moment is that my class Tracing needs the mesh information for calculating the flame position. For example I have to use mesh.C(). I don't know how to handle this, because I don't know how to deliver the mesh Information to my header file.
I tried to use a genererell objectRegistry in the the constructor Tracing(objectRegistry reg0,...), but there doesn't exist a .C() data.
Perhaps you know an example of an header-file that uses the mesh data in any way!?
Something i also do not understand is the declaration of a namespace
namespace Foam
{.....
...}
before the declaration of the class. Could you explain to me, why this is necessary?
Thanks a lot in advance!

Victor

Pass the mesh as an argument to the constructor:

header file:

Code:

        

class Tracing

{

    const fvMesh& mesh_;



    Tracing

    (

        const fvMesh& mesh

    );

}

source file:

Code:

Foam::Tracing::Tracing

(

    const fvMesh& mesh

)

:

    mesh_(mesh)

{}

Then you can use mesh_ in that class.

The Foam namespace isn't declared before the class,. The class is part of the namespace Foam. So Foam::regionProperties is its full name. In chtMultiRegionFoam.C you'll see:

regionProperties rp(runTime);

The full type would be Foam::regionProperties rp(runTime); but in the fvCFD.H file there's a using namespace Foam declaration.

Oh, thank you really much! This is exactly I was looking for!:)