2 c---------------------------------------------------------------------
3 c---------------------------------------------------------------------
4 subroutine l2norm ( ldx, ldy, ldz,
9 c---------------------------------------------------------------------
10 c---------------------------------------------------------------------
12 c---------------------------------------------------------------------
13 c to compute the l2-norm of vector v.
14 c---------------------------------------------------------------------
20 c---------------------------------------------------------------------
22 c---------------------------------------------------------------------
27 double precision v(5,-1:ldx+2,-1:ldy+2,*), sum(5)
29 c---------------------------------------------------------------------
31 c---------------------------------------------------------------------
33 double precision dummy(5)
46 dummy(m) = dummy(m) + v(m,i,j,k) * v(m,i,j,k)
52 c---------------------------------------------------------------------
53 c compute the global sum of individual contributions to dot product.
54 c---------------------------------------------------------------------
55 call MPI_ALLREDUCE( dummy,
64 sum(m) = sqrt ( sum(m) / ( (nx0-2)*(ny0-2)*(nz0-2) ) )