Noun, Suru verb, No-adjective
1. projectionMathematics
Wikipedia definition
2. Projection (mathematics)Generally speaking, in mathematics, a projection is a mapping of a set (or of a mathematical structure) which is idempotent, which means that a projection is equal to its composition with itself. A projection may also refer to a mapping which has a left inverse. Both notions are strongly related, as follows. Let p be an idempotent map from a set E into itself (thus p∘p = p) and F = p(E) be the image of p.
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