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Old   December 12, 2010, 00:02
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Quote:
Originally Posted by yashar.afarin View Post
Hi Su

how I could export my data so that I could specify and link for each point(cell centre) , the position(x,y,z) and velocity(u,v,w) variables of that point as a same file?
// include the head file
#include"OFstream.H"

//declare a object and out the variable you want. file.dat is the name of the //file you need.

OFstream os("file.dat");

forAll(mesh.C(), i)
{
os<<mesh.C()[i] <<" " <<u[i]<<endl;
}
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Old   January 17, 2011, 06:10
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Hi SU

thank you very much for all of your helps.
I would appreciate if you could answer my question.
I have calculated Umean by introducing a function at system/controlDict of my case and I can see its contour with paraFoam.
how I could export it (UMean) to a .dat file, similar to my last question about U ?
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Old   January 17, 2011, 06:56
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Quote:
Originally Posted by yashar.afarin View Post
Hi SU

thank you very much for all of your helps.
I would appreciate if you could answer my question.
I have calculated Umean by introducing a function at system/controlDict of my case and I can see its contour with paraFoam.
how I could export it (UMean) to a .dat file, similar to my last question about U ?
You don't have to process UMean. It should be in the time dir in your case.
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Old   January 17, 2011, 08:02
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Quote:
Originally Posted by su_junwei View Post
You don't have to process UMean. It should be in the time dir in your case.
yes, it's there but I want to export it to a file.dat. according to your reply I export U of each point but I don't know how I could do that again for UMean?
I would appreciate if you could help me.
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Old   January 17, 2011, 08:55
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Quote:
Originally Posted by yashar.afarin View Post
yes, it's there but I want to export it to a file.dat. according to your reply I export U of each point but I don't know how I could do that again for UMean?
I would appreciate if you could help me.
Just copy the internalField to a seperate file name *.dat

If you want to do it using a program, Just write a small tool for post processing. Read the file and write the internalField to a file

OFstream os("file.dat");

forAll(UMean.C(), i)
{
os<<mesh.C()[i] <<" " <<UMean[i]<<endl;
}
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Old   January 17, 2011, 09:35
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Quote:
Originally Posted by su_junwei View Post
Just copy the internalField to a seperate file name *.dat

If you want to do it using a program, Just write a small tool for post processing. Read the file and write the internalField to a file

OFstream os("file.dat");

forAll(UMean.C(), i)
{
os<<mesh.C()[i] <<" " <<UMean[i]<<endl;
}
thank you very much for your reply.
I wrote the code that you sent for me in applications/solvers/incompressible/pisoFoam/pisoFoam.C
but when I compiled it, an error would be reported:
write.H:55: error: ‘UMean’ was not declared in this scope

I cant understand what is the problem, plz give me help!

Last edited by yashar.afarin; January 17, 2011 at 10:41.
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Old   January 17, 2011, 11:43
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I am sorry. that was my silly reply. I know what you mean now. thanks for your reply.
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Old   February 22, 2011, 15:53
Default problems with mesh.cellCells()
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Quote:
Originally Posted by su_junwei View Post
Hi Khaled

mesh.cellCells()[cellI] gives the neighbours of cell cellI

su junwei
Hi Su

I'm just working on a possibility to refine locally on a selection of the mesh (blockMesh with refinementIterator). Since I have higher refinement levels I need to lay some buffer-layers around the selection. For this purpose I use the cellCells() function in multiple iterations.

My problem is that cellCells() does not recognize all neighbours of already refined cells (The refinement history I have implemented works fine and has no bugs) .

I'll give a little example:

- 8 cells (= refinement level 3) on the west side of a simple refined cell (= 2 cells f.e. cell A and B).
- this should give cell A as eastern neighbour for four of the tripple refined cells and cell B for the other four cells
- instead of this cellCells returns only cell A as eastern neighbour for all eight cells!!

And now the really big problem:

This bug is not reproduceable, since the correct recognition of all neighbours works fine in the mesh of forwardStep (tutorials/compressible/rhoCentralFo...), but not in the mesh of counterFlow2D (tutorials/combustion/reactingFoam...)
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Old   May 22, 2011, 20:22
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Quote:
Originally Posted by su_junwei View Post
// include the head file
#include"OFstream.H"

//declare a object and out the variable you want. file.dat is the name of the //file you need.

OFstream os("file.dat");

forAll(mesh.C(), i)
{
os<<mesh.C()[i] <<" " <<u[i]<<endl;
}
Hi Su,
Is it possible describe it more for me?
Where should be written this code and how should it be compiled?
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Old   May 22, 2011, 22:38
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just write it in the time cycle. os declaration can be written in creatFields. H

You can write it like the following code

if(runTime.outputTime()) //only write at outputTime point
{
forAll(mesh.C(), i)
{
os<<mesh.C()[i] <<" " <<u[i]<<endl;
}
}
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Old   January 7, 2012, 19:24
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Quote:
Originally Posted by kathrin_kissling View Post
Hi Pascal,

alternatively you can use

label labelOfClosestCell mesh.findCell(c y z);


Best Kathrin
Kathrin,

I am getting the following error when I use this:

Code:
transientSimpleFoam.C: In function ‘int main(int, char**)’:
transientSimpleFoam.C:123: error: expected initializer before ‘mesh’
transientSimpleFoam.C:124: error: ‘labelOfClosestCell’ was not declared in this scope
Any ideas why this is happening?

Thank you.
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Old   January 8, 2012, 13:08
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I think something is wrong with my formatting:
const point& location = (x,y,z); //your coordinates
label labelOfClosestCell=mesh.findCell(location);

Can you post your code?

Thanks!

Kathrin
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Old   January 8, 2012, 16:52
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Kathrin,

Thanks for your reply. It was indeed the problem with the way I specified my location. I got it working.
Thank you.
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Old   May 23, 2012, 07:18
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Hi, Junwei

I am trying to access the neighbour cells with parallel computing but it seems the cell which is placed adjacent to the interface between sub-domains does not recognize all neighbour cells.
I followed the same as you mentioned which is briefly (I am using OF-2.1.x),

mesh.cellCells()[cellI]

So I am wondering that you have a similar experience and is there any possible solution on this?

I also posted the question on this issue but I haven't got respose so far.

accessing neighbour cells in parallel computing


Thanks in advance.
Yusik
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Old   August 14, 2012, 10:56
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Quote:
Originally Posted by su_junwei View Post
Hi Pascal
you can use the following code

meshSearch ms(mesh);
label nearestCellIndex = ms.findNearestCell(p);

p is your point for searching nearest cell. nearestCellIndex is the cell index that you want.
Don't forget to include "meshSearch.H"

Junwei
Hi Junwei,

Could the p be a face in the internal field. If it could be, how can I define it?
Many thanks!

Wei
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Old   October 2, 2012, 12:39
Default X, Y and Z of each cell
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mahdiiowa is an unknown quantity at this point
hey, does anyone know how can I get the x, y and z of each cell?
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Old   September 23, 2013, 20:44
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Hi Junwei

As I see, the cellCells gives the list of index, my question is how could distinguish them?
thanks

Wei

Quote:
Originally Posted by su_junwei View Post
Hi Khaled

mesh.cellCells()[cellI] gives the neighbours of cell cellI

su junwei
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Old   September 25, 2013, 02:31
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The return value is a list of index of neighbor cells. cells can be distinguished from another from cell index, cell center, etc.
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Old   May 5, 2014, 15:38
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I'm confused about how to access a specific cell using cellCells. For example, how can I use cellCells to access the NORTH cell of each cell in my domain?

Here's an example of what I would like to do... I know that the code may not compile, I'm just trying to explain what I'm doing.

Code:
V=value; //V is a boundary field ('value' is calculated and varies across the domain)

forAll(U, celli)
{
U[celli]=V[celli];
U[NORTH of celli] = U[celli];
}
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Old   December 19, 2014, 02:58
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Quote:
Originally Posted by su_junwei View Post
Hi Pascal
you can use the following code

meshSearch ms(mesh);
label nearestCellIndex = ms.findNearestCell(p);

p is your point for searching nearest cell. nearestCellIndex is the cell index that you want.
Don't forget to include "meshSearch.H"

Junwei

Greeting Su

Is it possible to detail your hint more clearly?
I guess that the meshSearch.H should be added to the main code for instance reactingFoam.C . But what about

Code:
meshSearch ms(mesh); 
    label nearestCellIndex = ms.findNearestCell(p);
Where should I add these lines?

Thanks for your hints.


Best,
Bobi
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