Automatic Differentiation for Computational Finance.




Automatic differentiation (AD) is a powerful technique allowing to compute derivatives of a function given by a (potentially very large) piece of code. The basic principles of AD and some available tools implementing this technology are reviewed. AD is superior to divided differences because AD-generated derivative values are free of approximation errors, and superior to symbolic differentiation because code of very high complexity can be handled, in contrast to computer algebra systems whose applicability is limited to rather simple functions. In addition, the cost for computing gradients of scalar-valued functions with either divided differences or symbolic differentiation grows linearly with the number of variables, whereas the so-called reverse mode of AD can compute such gradients at constant cost.