Hi, I'm trying to view a particular row of a matrix. This 's what I do in my loops:
real(8):: vector(64) II=36 impl_mat_i=4. call MatSetValue(A_mat_uv,II,II,impl_mat_i,ADD_VALUES,ierr) call MatAssemblyBegin(A_mat_uv,MAT_FINAL_ASSEMBLY,ierr) call MatAssemblyEnd(A_mat_uv,MAT_FINAL_ASSEMBLY,ierr) call MatGetRow(A_mat_uv,II,PETSC_NULL,PETSC_NULL,vector,ierr) call MatRestoreRow(A_mat_uv,II,PETSC_NULL,PETSC_NULL,vector,ierr) When I look at "vector" using visual fortran debugger, I saw many different values in it, but I only added 1 value in 1 location. However, just before I use MatSetValue, I also called MatGetRow. It was initially all zero. But, if I use call MatSetValue(A_mat_uv,II,*1*,impl_mat_i,ADD_VALUES,ierr) instead of II, I see only 4 in vector(1). What happening? Where did all the other values come from? Also, is this the best way to view a particular row of a matrix? I tried to use call MatGetValues(A_mat_uv,1,36,64,1,vector,ierr) to get 1 row of values from the 36th row.There are 64 columns in total. Seems like it's the wrong way. Can you please show me the correct way? Thank you.
