A preconditioned conjugate gradient method for multiplicative half-quadratic image restoration (original) (raw)

Although programming is a difficult and creative activity, useful strategies and heuristics exist for solving programming problems. We analyse some of the most fundamental and productive among them; their knowledge and conscious application should help the programmers in constructing programs, both by stimulating their thinking and by helping them to recognise classical situations. The precise framework for the. analysis is provided by the specification language Z. For editorial reasons the description in some sections of this paper has had to be curtailed.