Reference

The Reference section is the precise API and configuration reference for Exasim. It complements the tutorials and conceptual guides by documenting exact interfaces, accepted input forms, runtime file semantics, model functions, and build-system options.

Use this section when you need to answer questions such as:

• Which pdeapp.txt keys are recognized?
• Which frontend pde fields control a runtime option?
• Which model functions are required by Text2Code?
• What arguments does a boundary or source function receive?
• Which CMake targets and options are installed?
• How are parameter sweeps and postprocessing configured exactly?

Relationship to Other Documentation

Section	Use it for
Quickstart	First successful installation and simulation.
Application Modes	User workflows such as built-in, shared-library, sweep, and postprocess modes.
Using AI Tools	Prompting AI assistants to generate examples or modify code safely.
Physics Models	Mathematical meaning of ModelC, ModelD, ModelW, EOS, AV, and coupling.
Theory	DG/HDG/LDG, solvers, preconditioning, and numerical algorithms.
Internals	Implementation architecture and contributor workflow.
Reference	Exact fields, functions, signatures, file formats, and build options.

Reference Map

Page	Contents
pdeapp reference	pdeapp.txt keys, frontend pde fields, defaults, accepted values, interactions.
pdemodel reference	pdemodel.txt declarations, function blocks, generated outputs.
Model contract	C++ model/provider contract and data layout conventions.
Model functions	Function-by-function interface reference for fluxes, sources, boundaries, initial conditions, visualization, and QoI.
Equations of state	EOS callbacks and derivative interfaces.
Boundary conditions	Boundary IDs, expressions, Ubou, Fbou, and HDG boundary residuals.
Source terms	Volume source and auxiliary source interfaces.
Auxiliary equations	w equations, Sourcew, initialization, and coupling to flux/source/EOS.
Parameter sweeps	Frontend and standalone sweep configuration, warm-start, metadata, outputs.
Postprocessing	Postprocessing controls, saved solution replay, visualization and QoI outputs.
Text2Code	Text2Code executable behavior, parser format, output files, and examples.
CMake	Superbuild options, install options, exported targets, components, examples.
Glossary	Common Exasim terms and abbreviations.

Required Versus Optional

This Reference uses the following conventions:

• Required means the parser or runtime needs the field for the workflow.
• Optional means Exasim has a default or the feature is inactive when the field is omitted.
• Frontend-only means the setting exists in MATLAB/Python/Julia helper logic but is not parsed from pdeapp.txt or stored in app.bin.
• Runtime means the setting is serialized into Exasim binary input files and affects standalone C++ execution.

AI-Assisted Development

AI tools should treat this Reference as the source of truth for exact names, interfaces, and accepted values. When asking an AI assistant to create or modify an Exasim application, include links or excerpts from the relevant Reference pages and ask it to preserve the documented interfaces.

See Using AI Tools for prompt templates and validation guidance.