Fundamentality of Ridge Functions
نویسنده
چکیده
For a given integer d, 1 ≤ d ≤ n − 1, let Ω be a subset of the set of all d × n real matrices. Define the subspace M(Ω) = span{g(Ax) : A ∈ Ω, g ∈ C(IR, IR)} . We give necessary and sufficient conditions on Ω so that M(Ω) is dense in C(IR, IR) in the topology of uniform convergence on compact subsets. This generalizes work of Vostrecov and Kreines. We also consider some related problems. §
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