Abstract
We are interested in determining the effective content of the Krein-Milman theorem. In this paper we discuss the finite dimensional case. We design an algorithm,(Algorithm E) to locate the set of extreme points of a convex compact Turing located set K ⫅R q. A sequence of approximating convex hulls for K is computed. Several lemmas about the extreme points of a convex compact set K are proved to guarantee the correctness of the algorithm. The condition that K is Turing located is necessary for the success of Algorithm E, that is, Algorithm E is effective if and only if K is Turing located. Algorithm E ia an effective version of the finite dimensinal Krein-Milman Theorem. A sequel will investigate the effective content of the KreinMilman theorem in effectively presented metric spaces.
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© 1994 Springer-Verlag Berlin Heidelberg
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Ge, X., Nerode, A. (1994). On extreme points of convex compact turing located set. In: Nerode, A., Matiyasevich, Y.V. (eds) Logical Foundations of Computer Science. LFCS 1994. Lecture Notes in Computer Science, vol 813. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-58140-5_12
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DOI: https://doi.org/10.1007/3-540-58140-5_12
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