Dear all,


I try to extract the values of a function h, at some specific positions with the function .at() .


I define a coarse mesh with

Nx_fine = int(Lx/0.4) + 1               

Ny_fine = int(Ly/0.4) + 1            

coarse_mesh = RectangleMesh(Nx_coarse,Ny_coarse,Lx,Ly,quadrilateral=True)

coarse_V = FunctionSpace(coarse_mesh, "CG", 1)

coarse_h = Function(coarse_V, name="h")

V_vec_c = VectorFunctionSpace(coarse_mesh, "CG", 1)

coarse_points = Function(V_vec_c , name="coarse_points")

coarse_points.interpolate(SpatialCoordinate(coarse_mesh))


Then I define a finer mesh with

Nx_fine = int(Lx/0.1) + 1               

Ny_fine = int(Ly/0.1) + 1             

fine_mesh = RectangleMesh(Nx_fine,Ny_fine,Lx,Ly,quadrilateral=True)

fine_V = FunctionSpace(fine_mesh, "CG", 1)

fine_h = Function(fine_V, name="h")


Then I load an h5 function into fine_h (defined on the same function space) with

dumb_file_fine = DumbCheckpoint(save_path+"fine/h_0", mode=FILE_READ)

dumb_file_fine.load(fine_h)

dumb_file_fine.close()


But then, when I try to extract the values of fine_h at the coordinates of coarse_mesh with

coarse_data_fine = fine_h.at(coarse_points.dat.data_ro)


I get this error:

[0]PETSC ERROR: ------------------------------------------------------------------------

[0]PETSC ERROR: Caught signal number 11 SEGV: Segmentation Violation, probably memory access out of range

[0]PETSC ERROR: Try option -start_in_debugger or -on_error_attach_debugger

[0]PETSC ERROR: or see http://www.mcs.anl.gov/petsc/documentation/faq.html#valgrind

[0]PETSC ERROR: or try http://valgrind.org on GNU/linux and Apple Mac OS X to find memory corruption errors

[0]PETSC ERROR: configure using --with-debugging=yes, recompile, link, and run 

[0]PETSC ERROR: to get more information on the crash.

--------------------------------------------------------------------------

MPI_ABORT was invoked on rank 0 in communicator MPI_COMM_WORLD

with errorcode 59.


NOTE: invoking MPI_ABORT causes Open MPI to kill all MPI processes.

You may or may not see output from other processes, depending on

exactly when Open MPI kills them.

--------------------------------------------------------------------------


Is someone familiar with this error ?

Thanks,
Floriane