Thank you all for your replies. All the best,,
On Sep 21, 2014, at 11:55 AM, "Jed Brown" <[email protected]> wrote: > Feng Shi <[email protected]> writes: > >> Hi all, >> >> When setting the Mat indices, like the example: >> src/ts/examples/tutorials/ex10, I noticed that on line >> >> 508: col[0] = i-1; >> 509: col[1] = i; >> 510: col[2] = i+1<info.mx ? i+1 : -1; >> 511: >> MatSetValuesBlocked<http://www.mcs.anl.gov/petsc/petsc-current/docs/manualpages/Mat/MatSetValuesBlocked.html#MatSetValuesBlocked>(B,1,&i,3,col,&K[0][0],INSERT_VALUES<http://www.mcs.anl.gov/petsc/petsc-current/docs/manualpages/Sys/INSERT_VALUES.html#INSERT_VALUES>); >> >> How about the case that when i=0, then col[0]=-1 and i=info.mx then >> col[2]=-1? >> My question is, is the Mat default indices starting from -1? > > No, matrix insertion ignores negative indices.
