# Object is in wrong state **URL:** \ **Category:** General Discussion\ **Created:** [August 9, 2021, 1:56pm UTC](https://community.freefem.org/t/object-is-in-wrong-state/1145 "2021-08-09T13:56:44Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![Mik](https://avatars.discourse-cdn.com/v4/letter/m/958977/32.png) [@Mik](https://community.freefem.org/u/Mik)\ **Post date:** [August 9, 2021, 1:56pm UTC](https://community.freefem.org/t/object-is-in-wrong-state/1145/1 "2021-08-09T13:56:44Z")
Dear members, I have stumbled upon a Petsc error. Out of my full mesh, I am trying to solve the heat transfer problem on selected volume numbers defined as reg. Apart from these volume numbers, the rest are not solving for the heat transfer. So T=Tinitial for the unused volume numbers. While adding the selected volume numbers in int3d(Th1, **reg** , qfV=qfV1), I am getting a Petsc error: Object is in wrong state I think it is due to the fact that I am trying to solve in a selected volume numbers because if I remove this it works perfectly. How to overcome this error? I am attaching a test version of my problem in the attachment. Thanks in advance for your help and time. [https://drive.google.com/drive/folders/1xARiZzE3yTov5bIwE2EXL3UpUVhQKWGn?usp=sharing](https://drive.google.com/drive/folders/1xARiZzE3yTov5bIwE2EXL3UpUVhQKWGn?usp=sharing) ---
**Author:** ![prj](https://avatars.discourse-cdn.com/v4/letter/p/ecae2f/32.png) [@prj](https://community.freefem.org/u/prj)\ **Post date:** [August 9, 2021, 2:09pm UTC](https://community.freefem.org/t/object-is-in-wrong-state/1145/2 "2021-08-09T14:09:20Z")
Always look at the error message in full please… ```auto [1]PETSC ERROR: Object is in wrong state [1]PETSC ERROR: Matrix is missing diagonal entry 31 ``` Furthermore, if you look at the trace, you’ll see something like: ```auto [1]PETSC ERROR: #1 MatILUFactorSymbolic_SeqAIJ() at /ccc/work/cont003/rndm/rndm/petsc/src/mat/impls/aij/seq/aijfact.c:1697 [1]PETSC ERROR: #2 MatILUFactorSymbolic() at /ccc/work/cont003/rndm/rndm/petsc/src/mat/interface/matrix.c:6942 [1]PETSC ERROR: #3 PCSetUp_ILU() at /ccc/work/cont003/rndm/rndm/petsc/src/ksp/pc/impls/factor/ilu/ilu.c:144 [1]PETSC ERROR: #4 PCSetUp() at /ccc/work/cont003/rndm/rndm/petsc/src/ksp/pc/interface/precon.c:1016 [1]PETSC ERROR: #5 KSPSetUp() at /ccc/work/cont003/rndm/rndm/petsc/src/ksp/ksp/interface/itfunc.c:406 [1]PETSC ERROR: #6 PCSetUpOnBlocks_BJacobi_Singleblock() at /ccc/work/cont003/rndm/rndm/petsc/src/ksp/pc/impls/bjacobi/bjacobi.c:617 [1]PETSC ERROR: #7 PCSetUpOnBlocks() at /ccc/work/cont003/rndm/rndm/petsc/src/ksp/pc/interface/precon.c:1047 [1]PETSC ERROR: #8 KSPSetUpOnBlocks() at /ccc/work/cont003/rndm/rndm/petsc/src/ksp/ksp/interface/itfunc.c:214 [1]PETSC ERROR: #9 KSPSolve_Private() at /ccc/work/cont003/rndm/rndm/petsc/src/ksp/ksp/interface/itfunc.c:851 [1]PETSC ERROR: #10 KSPSolve() at /ccc/work/cont003/rndm/rndm/petsc/src/ksp/ksp/interface/itfunc.c:1084 ``` You think you are using `-pc_type hypre`, but in reality your are not, since there is a typo in your sparams, `--pc_type` → `-pc_type`. Your problem is singular since you are only integrating on part of the domain. This is unlikely to work, even with `-pc_type hypre`. ---
**Author:** ![Mik](https://avatars.discourse-cdn.com/v4/letter/m/958977/32.png) [@Mik](https://community.freefem.org/u/Mik)\ **Post date:** [August 10, 2021, 8:05am UTC](https://community.freefem.org/t/object-is-in-wrong-state/1145/3 "2021-08-10T08:05:47Z")
Thanks for the reply. Is there any solution or suggestion for this problem? ---
**Author:** ![prj](https://avatars.discourse-cdn.com/v4/letter/p/ecae2f/32.png) [@prj](https://community.freefem.org/u/prj)\ **Post date:** [August 10, 2021, 10:25am UTC](https://community.freefem.org/t/object-is-in-wrong-state/1145/4 "2021-08-10T10:25:10Z")
With PETSc, there is almost always a solution, which is almost always in one of the example from the distribution. Please see [FreeFem-sources/restriction-2d-PETSc.edp at develop · FreeFem/FreeFem-sources · GitHub](https://github.com/FreeFem/FreeFem-sources/blob/develop/examples/hpddm/restriction-2d-PETSc.edp). In your case, [line 19](https://github.com/FreeFem/FreeFem-sources/blob/develop/examples/hpddm/restriction-2d-PETSc.edp#L19) should read `Ph cond = region == reg;`, and then remove the `reg` inside the integrals. ---
**Author:** ![Mik](https://avatars.discourse-cdn.com/v4/letter/m/958977/32.png) [@Mik](https://community.freefem.org/u/Mik)\ **Post date:** [August 13, 2021, 8:32am UTC](https://community.freefem.org/t/object-is-in-wrong-state/1145/5 "2021-08-13T08:32:23Z")
Are you suggesting by truncating the mesh? Then I already have one approach with FreeFEM which works beautifully with **trunc** command. I am trying a new approach with the region-based integration, despite the presence of the complete mesh. It works good with **solve** but not when do it with **varf**. ---
**Author:** ![prj](https://avatars.discourse-cdn.com/v4/letter/p/ecae2f/32.png) [@prj](https://community.freefem.org/u/prj)\ **Post date:** [August 13, 2021, 8:57am UTC](https://community.freefem.org/t/object-is-in-wrong-state/1145/6 "2021-08-13T08:57:19Z")
Why do you need a new approach? Is there a real need for the region-based integration? One way to bypass the problem may be to add a small regularization to make the problem definite, e.g., `int3d(Th, !reg)(eps * u * v)`, with a small `eps`.