Precise Fixpoint Computation Through Strategy Iteration

  title={Precise Fixpoint Computation Through Strategy Iteration},
  author={Thomas Gawlitza and Helmut Seidl},
We present a practical algorithm for computing least solutions of systems of equations over the integers with addition, multiplication with positive constants, maximum and minimum. The algorithm is based on strategy iteration. Its run-time (w.r.t. the uniform cost measure) is independent of the sizes of occurring numbers. We apply our technique to solve systems of interval equations. In particular, we show how arbitrary intersections as well as full interval multiplication in interval equations… 
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Least and Greatest Solutions of Equations over N
  • H. Seidl
  • Mathematics, Computer Science
    Nord. J. Comput.
  • 1996
Efficient algorithms in case of computing least and greatest solutions of a system of equations xi = fi, i = 1,..., n, over N, where the right hand sides fi are expressions built up from constants and variables by various sets of operations are presented.
A class of polynomially solvable range constraints for interval analysis without widenings
A Policy Iteration Algorithm for Computing Fixed Points in Static Analysis of Programs
A policy iteration algorithm for monotone self-maps of complete lattices for lattices arising in the interval abstraction of values of variables is introduced and analyzed.
Complexity of linear programming
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