[benk]

Hi, I'm trying to get the value at the corner of a 2D mesh. I can easily get the values along the boundary by doing something like:

label topWall = 2DMesh.boundaryMesh().findPatchID("topWall");
fixedGradientFvPatchScalarField& bufferC = refCast<fixedGradientFvPatchScalarField>(C2D.boundaryField()[topWall]);
scalarField& valC  = bufferC;
	
forAll (valCsPositive, i)
{
cBoundary[i] =   C2D.boundaryField()[topWall][i];
}

But this doesn't include the values at the corners. How can I get these?

I've tried something like this which I found from Retrieving boundary patch values adjacent to a given cell:

vector probePoint(x,y,z); //these are the coordinates of the value I need
label probeCell = mesh.findCell(probePoint); // this is the nearest cell to the point that I need
const cell& c = mesh.cells()[probeCell]; // a cell is a list of faces 

forAll (c, i) 
{ 
// This gives you the patch ID for a face. If the face is internal, you get -1 
label patchID = mesh.boundaryMesh().whichPatch(c[i]); 

if (patchID > -1) 
{ 
label faceID = mesh.boundaryMesh()[patchID].whichFace(c[i]); 

Info << "values=" << field.boundaryField()[patchID][faceID] << endl;

} 
}

But this will only give me the values at the patches of the specified cell (not the corner) and moreover, it gives me a segmentation fault during runtime after spitting out the values at the patches.

[julien.decharentenay]

I am no expert in OpenFoam. But it looks like you might be trying to access a node value, whilst OpenFoam only let you access the face values.