Noun, Suru verb, Transitive verb
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.
Read “Projection (mathematics)” on English Wikipedia
Read “射影” on Japanese Wikipedia
Read “Projection (mathematics)” on DBpedia


to talk about this word.