High Performance Computing 1
S(j)
•Here we consider a so-called weighted Jacobi smoothing operator S(i).
•Pure Jacobi would replace the j-th component of the approximate solution x(i) by the weighted average:
•x(i)(j) = .5*( x(i)(j-1) + x(i)(j+1) + 4^i * b(i)(j) )
•           = x(i)(j) + .5*( x(i)(j-1) - 2*x(i)(j) + x(i)(j+1)
•                   + 4^i * b(i)(j) )
•Weighted Jacobi instead uses
•x(i)(j) = x(i)(j) + w*.5*( x(i)(j-1) - 2*x(i)(j) + x(i)(j+1)
•                   + 4^i * b(i)(j) )
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