[petsc-users] DM/DMPlex Issue from DM vector access

[Ferrand, Jesus A.]

Dear PETSc Team:

I am a new PETSc user who is working on an FEA code and ran into an issue pertaining to DMPlex.

I have a gmsh mesh file that I import using "DMPlexCreateGmshFromFile()." I then fetch the XYZ coordinates of the nodes from this mesh using "DMGetCoordinatesLocal()." Deeper into the code, I have a call to "DMPlexGetTransitiveClosure()" inside a loop that scans the cells (I think you guys refer to it as "depth-3") to reference nodes. Here's the catch: If I attempt to reference the array from the vector (Vec) in the call to "DMGetCoordinatesLocal()" by using something like "VecGetArray()," or "VecGetArrayRead()," the call to "DMPlexGetTransitiveClosure()" errors-out with a segmentation fault. I need access to that vector's stored XYZ-data because I'm using my own finite element scripts. I have no clue as to why this is happening. Maybe it is a newbie mistake and I am forgetting to restore some memory?

Code, error message, and gmsh files are attached.
Your help is much appreciated.

Machine Type: HP Laptop
C-compiler: Gnu C
OS: Ubuntu 20.04
PETSc version: 3.16.0
MPI Implementation: MPICH

Sincerely:

J.A. Ferrand

Embry-Riddle Aeronautical University - Daytona Beach FL

M.Sc. Aerospace Engineering | May 2022

B.Sc. Aerospace Engineering

B.Sc. Computational Mathematics



Sigma Gamma Tau

Tau Beta Pi

Honors Program



Phone: (386)-843-1829

Email(s): ferranj2 at my.erau.edu

    jesus.ferrand at gmail.com
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