Basic HTML version of Foils prepared 8 November 1995

Foil 41 Jacobi Relaxation for Over Relaxation Parameter w =1/2

From CPS615 Module on Iterative PDE Solvers CPS615 Basic Simulation Track for Computational Science -- Fall Semester 95. by Geoffrey C. Fox


For w=1/2, one has
x(k+1) =1/2[x(k) + x(k+1 ) ] where J denotes Pure Jacobi
and subscript JOR stands for Jacobi Over Relaxation again
This has "update" matrix in two dimensions
xpoint = 1/2 xpoint + 1/8 times x of four neighbors
We now "couple" even and odd grid points which were decoupled in original Jacobi
Corresponding eigenvalue of most rapidly varying eigenfunction is
now lJOR|min ~ 0
not lJOR|min ~ -1 as before



© on Tue Oct 28 1997