Downstream C++ project

NEML2 core capabilities are implemented as a library, not a program. As a library, it will be used by another C++ program to parse and evaluate a material model defined in an input file. Boilerplate for the C++ program can be found in this set of tutorials, and external project integration is documented in the installation guide.

The Runner

We acknowledge the common need to use NEML2 as a standalone program and therefore provide two convenient options for users to effectively use NEML2 as a standalone program, with the first option being the NEML2 Runner.

As documented in build customization, the "runner" preset or the NEML2_RUNNER CMake option can be used to create a simple "runner" program for parsing, diagnosing, and running NEML2 material models.

cmake --preset runner -S .

cmake --build --preset runner

Once the runner is built (and/or installed), an executable named runner will be placed under the build directory (or the installation directory). Invoking the executable without any additional argument or with the -h or --help argument will print out the usage message:

Usage: runner [--help] [--version] {diagnose,inspect,run,time}
 
Optional arguments:
  -h, --help     shows help message and exits
  -v, --version  prints version information and exits
 
Subcommands:
  diagnose      Run diagnostics on a driver or a model from an input file.
  inspect       Summarize the structure of a model.
  run           Run a driver from an input file.
  time          Time the execution of a driver from an input file.

See the subcommand help messages for further details.

Python script

The other option to evaluate NEML2 material models is to use the NEML2 Python package. As mentioned in the installation guide, NEML2 also provides an experimental Python package which provides bindings for the primitive tensors and parsers for deserializing and running material models. This set of tutorials describes the usage of the package.

Table of Contents

Downstream C++ project

The Runner

Python script