Numerical invariants through convex relaxation and max-strategy iteration

  title={Numerical invariants through convex relaxation and max-strategy iteration},
  author={Thomas Gawlitza and Helmut Seidl},
  journal={Formal Methods in System Design},
We present an algorithm for computing the uniquely determined least fixpoints of self-maps on $\overline{\mathbb{R}}^{n}$ (with $\overline{\mathbb{R}} = \mathbb{R} \cup\{ \pm\infty\}$) that are point-wise maximums of finitely many monotone and order-concave self-maps. This natural problem occurs in the context of systems analysis and verification. As an example application we discuss how our method can be used to compute template-based quadratic invariants for linear systems with guards. The… 
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