Successive over relaxation is used in many HPF kernels:
DO j = 2,n-1 DO i = 2,n-1 a(i,j)=(omega/4)*(a(i,j-1)+a(i,j+1)+ & a(i-1,j)+a(i+1,j))+(1-omega)*a(i,j) END DO END DO
The calculation of a(i,j) uses its 4 neighbours.
BLOCK distribution in both dimensions will be the most effective distribution here.
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