[petsc-users] A question of DMPlexGetAdjacency

[leejearl]

Hi all:

     I am not sure the using of the function "DMPlexGetAdjacency".

     My codes are as follows:

     PetscInt adj, *adjSize=NULL;

     ierr = DMPlexGetAdjacency(dm, p,  &adj, &adj);

     Sometimes, The above codes works. But, it always gets an error:

[0]PETSC ERROR: --------------------- Error Message 
--------------------------------------------------------------
[0]PETSC ERROR: Petsc has generated inconsistent data
[0]PETSC ERROR: Invalid mesh exceeded adjacency allocation (1)
[0]PETSC ERROR: See http://www.mcs.anl.gov/petsc/documentation/faq.html 
for trouble shooting.
[0]PETSC ERROR: Petsc Development GIT revision: v3.7.4-1864-ga10654c  
GIT Date: 2016-11-01 22:25:06 -0500
[0]PETSC ERROR: ./cavity on a arch-linux2-c-debug named leejearl by 
leejearl Mon Nov 14 22:57:03 2016
[0]PETSC ERROR: Configure options --prefix=/home/leejearl/Install/Petsc 
--with-mpi-dir=/home/leejearl/Install/openmpi/1.8.5_gnu 
--download-exodusii=../externalpackages/exodus-5.24.tar.bz2 
--download-netcdf=../externalpackages/netcdf-4.3.2.tar.gz 
--download-hdf5=../externalpackages/hdf5-1.8.12.tar.gz 
--download-triangle=../externalpackages/Triangle.tar.gz 
--download-sowing=../externalpackages/git.sowing.tar.gz
[0]PETSC ERROR: #1 DMPlexGetAdjacency_Cone_Internal() line 193 in 
/home/leejearl/Software/petsc/petsc/src/dm/impls/plex/plexdistribute.c
[0]PETSC ERROR: #2 DMPlexGetAdjacency_Internal() line 298 in 
/home/leejearl/Software/petsc/petsc/src/dm/impls/plex/plexdistribute.c
[0]PETSC ERROR: #3 DMPlexGetAdjacency() line 372 in 
/home/leejearl/Software/petsc/petsc/src/dm/impls/plex/plexdistribute.c
[0]PETSC ERROR: #4 CalcConVarGradient() line 98 in 
/home/leejearl/Desktop/PETSc/gkscavity/cavity.c


     Can anyone help me with the origin of the error? or help me with a 
sample code of the use of function "DMPlexGetAdjacency".

     Thanks

leejearl