| 释义 |
Definition of direct sum in English: direct sumnoun Mathematics A set regarded formally as the sum of sets X₁,…,Xₙ, consisting of ordered n-tuples (x₁,…,xₙ), where xi ∈ Xi, and distinguished from a direct product only in the case of an infinite number of sets, the direct sum consisting only of sequences containing a finite number of non-zero elements.
Origin Early 20th century; earliest use found in Proceedings of the London Mathematical Society. Definition of direct sum in US English: direct sumnoun Mathematics A set regarded formally as the sum of sets X₁,…,Xₙ, consisting of ordered n-tuples (x₁,…,xₙ), where xi ∈ Xi, and distinguished from a direct product only in the case of an infinite number of sets, the direct sum consisting only of sequences containing a finite number of non-zero elements.
Origin Early 20th century; earliest use found in Proceedings of the London Mathematical Society. |