**Defined in theory: Unary-scalar-functions****Source code: unary-scalar-functions.lisp****Also defined in:**Kif-numbers, Physical-quantities, Scalar-quantities, Basic-matrix-algebra, Tensor-quantities

**Documentation:**Defines the specialization of the QUANTITY addition operator + for unary-scalar-function-quantitys. This now works when the exact-domains of the addends are overlapping.

**Instance-Of:**Function, Relation-extended-to-function-quantities

(=> (And (Unary-Scalar-Function-Quantity ?X) (Unary-Scalar-Function-Quantity ?Y) (+ ?X ?Y ?Z)) (Unary-Scalar-Function-Quantity ?Z))