What is Calculus?
A branch of mathematics used to understand how values inside a function change.
Integrals
Functional Integrals
Derivatives
Derivatives deal with rates of change of variables in a function. Functions can also become Ordinary Differential Equations (ODEs) and Partial Differential Equations (PDEs).
Functional Derivatives
Functional derivatives are analogous to ordinary derivatives. Whereas ordinary derivatives focus on the change in function with respect to a change in variables, functional derivatives consider the change in functional with respect to a function.
Functional derivatives follow the structure:
which describes the rate of change of a functional when the input is changed a little bit (hence the ).