which of the functional groups behaves as a base

Functional neurologic disorder (FND) reflects functional network dysregulation rather than structural pathology. Effective treatment focuses on education, expectation setting, family engagement and graded rehabilitation to restore movement and participation. FND is a condition in which neurological ... The word "functional" is just short for "linear function which codomain is the scalar field". So no, the evaluation is not a functional if the codomain is a vector space different from the field. In the context of functional analysis, a functional is a function from a vector space to its base field (usually $\mathbb {R}$ or $\mathbb {C}$). In many important cases they are linear, but this is not always the case. In the context of normed vector spaces or more generally topological vector spaces, they are also often continuous, but again this is not always the case. Much less commonly ...