# auto_deriv: Tool for automatic differentiation of a Fortran code

## Description

Abstract auto_deriv is a module comprised of a set of fortran 95 procedures which can be used to calculate the first and second partial derivatives (mixed or not) of any continuous function with many independent variables. The mathematical function should be expressed as one or more fortran 77/90/95 procedures. A new type of variables is defined and the overloading mechanism of functions and operators provided by the fortran 95 language is extensively used to define the differentiation rules. Proper (... Title of program: AUTO_DERIV Catalogue Id: ADLS_v2_0 Nature of problem The need to calculate accurate derivatives of a multivariate function frequently arises in computational physics and chemistry. The most versatile approach to evaluate them by a computer, automatically and to machine precision, is via user-defined types and operator overloading. AUTO_DERIV is a Fortran 95 implementation of them, designed to evaluate the first and second derivatives of a function of many variables. Versions of this program held in the CPC repository in Mendeley Data ADLS_v1_0; AUTO_DERIV; 10.1016/S0010-4655(99)00513-5 ADLS_v2_0; AUTO_DERIV; 10.1016/j.cpc.2010.06.043 This program has been imported from the CPC Program Library held at Queen's University Belfast (1969-2019)