# PlanetPhysics/Preadditive Functor

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A functor between two preadditive categoriesFailed to parse (unknown function "\A"): {\displaystyle \mathcal{\A_P}}andFailed to parse (unknown function "\A"): {\displaystyle \mathcal{\A'_P}}is called a(pre) additive (or preadditive) functor,

if for any pair of morphisms **Failed to parse (unknown function "\A"): {\displaystyle f, g \in Hom_{\mathcal{\A_P}}(X,Y)}**
one has that .