functional (original) (raw)

Definition

Discussion

Examples of functionals include the integral and entropy. A functional f is often indicated by the use of brackets, T⁢[x] rather than T⁢(x).

The linear functionals are those functionals T that

• •
  T⁢(x+y)=T⁢(x)+T⁢(y)
• •
  T⁢(c⁢x)=c⁢T⁢(x)

for any c∈K, x,y∈V.