46-XX Functional analysis {For manifolds modeled on topological linear spaces, see 57Nxx, 58Bxx} 137849
46Cxx Inner product spaces and their generalizations, Hilbert spaces {For function spaces, see 46Exx} 5422
46C05 Hilbert and pre-Hilbert spaces: geometry and topology (including spaces with semidefinite inner product) 2108