On Diagonally Relaxed Orthogonal Projection Methods
نویسندگان
چکیده
We propose and study a block-iterative projections method for solving linear equations and/or inequalities. The method allows diagonal component-wise relaxation in conjunction with orthogonal projections onto the individual hyperplanes of the system, and is thus called diagonally-relaxed orthogonal projections (DROP). Diagonal relaxation has proven useful in accelerating the initial convergence of simultaneous and block-iterative projection algorithms but until now it was available only in conjunction with generalized oblique projections in which there is a special relation between the weighting and the 1 Figure 1: The fully-discretized model of the image reconstruction problem.
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ورودعنوان ژورنال:
- SIAM J. Scientific Computing
دوره 30 شماره
صفحات -
تاریخ انتشار 2008