direct sum of modules

The symbol ⊕ redirects here; it is also the astrological and astronomical symbol for Earth, and a symbol for the Exclusive disjunction. In abstract algebra, the direct sum is a construction which combines several modules into a new, larger module. The result of the direct summation of modules is the "smallest general" module which contains the given modules as subspaces. This is an example of a coproduct. Contrast with the direct product, which is the dual notion.
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