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Computing (FOLDOC) dictionary (also found in English - Vietnamese, English - English (Wordnet), French - Vietnamese)
injection
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1. mathematics A function, f : A -@# B, is injective or
one-one, or is an injection, if and only if
for all a,b in A, f(a) = f(b) =@# a = b.
I.e. no two different inputs give the same output (contrast
many-to-one). This is sometimes called an embedding. Only
injective functions have left inverses f' where f'(f(x)) = x,
since if f were not an injection, there would be elements of B
for which the value of f' was not unique. If an injective
function is also a surjection then is it a bijection.
2. reduction An injection function is one which takes
objects of type T and returns objects of type C(T) where C is
some type constructor. An example is