IV.39 Algebraic Geometry
نویسنده
چکیده
integrality constraints of a description as an optimization problem over variables in Rn. Linear programming formulations can imply polynomial-time algorithms even if they have exponentially many variables or constraints (by the equivalence of optimization and separation). Linear relaxations can be strengthened by adding further linear constraints, called cutting planes. One can also consider nonlinear relaxations. In particular, semidefinite relaxations have been used for some approximation algorithms. Of course, after solving a relaxation, the originally required property must be restored somehow. If a fractional solution is made integral, this is often called rounding. Note that rounding is used here in a general sense (deriving an integral solution from a fractional one), and not specifically meaning rounding to the nearest integer. Sophisticated rounding algorithms for various purposes have been developed.
منابع مشابه
On the Smoothness of Functors
In this paper we will try to introduce a good smoothness notion for a functor. We consider properties and conditions from geometry and algebraic geometry which we expect a smooth functor should has.
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