The modern technical definition of a functional is a function from a vector space into the scalar field. For example, finding the length of a vector is a (non-linear) functional, or taking a vector and returning the 3rd coordinate (relative to some basis) is a (linear) functional. But in a classical sense, functional is an antiquated term for a function that takes a function as input. For ...
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 ...
Overview Functional dyspepsia is a term used to describe a lingering upset stomach that has no obvious cause. Functional dyspepsia (dis-PEP-see-uh) also is called nonulcer dyspepsia. Functional dyspepsia is common. It is a constant condition, but symptoms don't happen all the time. Symptoms are like those of an ulcer. They include pain or discomfort in the upper belly, bloating, belching and ...
Treatment Functional dyspepsia that can't be managed with lifestyle changes may need treatment. Treatment depends on symptoms. It may combine medicines and behavior therapy. Medicines Some medicines may help manage symptoms of functional dyspepsia. They include: Gas remedies that are available without a prescription.
Functional neurologic disorder — a newer and broader term that includes what some people call conversion disorder — features nervous system (neurological) symptoms that can't be explained by a neurological disease or other medical condition.
Treatment for functional neurologic disorder will depend on your particular signs and symptoms. For some people, a multispecialty team approach that includes a neurologist; psychiatrist or other mental health professional; speech, physical and occupational therapists; or others may be appropriate.
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 ...
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.