This repository provides a Fortran Package Manager (fpm) compatible version of the dual number implementation for arbitrary-order automatic differentiation (DNAOAD).

⚠️ Note: The core code is essentially the same as in the original repository fpenunuri/DNAOAD, with some changes for FPM compatibility. For more information, see the preprint: 📄 arXiv:2501.04159

• src/ — Fortran source modules
• app/ — Executable programs
• docs/ — Documentation of module functions
• fpm.toml — Project configuration file

• A Fortran compiler (e.g., gfortran, ifx)
• A recent version of fpm

To install fpm, visit:
👉 https://github.com/fortran-lang/fpm

From the project root:

FPM_FC=ifx fpm build

FPM_FC=ifx fpm run ex1

By default, MAX_ORDER_DUALZN = 5. The example ex2 requires at least 10:

FPM_FC=ifx fpm run --flag "-DMAX_ORDER_DUALZN=10" ex2

To build and run using real128 precision:

FPM_FC=ifx fpm build --flag "-DUSE_REAL128"

Run ex2 with higher derivative order:

FPM_FC=ifx fpm run --flag "-DUSE_REAL128 -DMAX_ORDER_DUALZN=10" ex2