lammps/tools/json

This folder contains files and tools for creating, modifying, and validating files in JSON format. This is work in progress while we are adding JSON support

JSON file format validation.

JSON-Schema files

We provide schema files for the file formats that LAMMPS supports following the specifications available on JSON-Schema webpage. The following files are currently available.

• molecule-schema.json Schema file for the JSON format molecule files.

These files provide a concise description of the hierarchy and supported fields in JSON file formats. Thus they provide a detailed documentation and can also be used for validating JSON files.

Validation of JSON files

There are multiple tools for JSON file validation available. Here are instructions for how to use a tool called check-jsonschema which is available via PyPi.

# Installation into a virtual environment.
# Once installed only the activation should be needed
python3 -m venv validate-json
source validata-json/bin/activate
pip install --upgrade pip
pip install check-jsonschema

# Validation of two molecule files "rxn1.json" and "twomols.json" with "molecule-schema.json"
check-jsonschema --schemafile molecule-schema.json rxn1.json twomols.json

If the files are conforming there should be the output:

ok -- validation done

Otherwise details about the non-conforming fields are given.

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updated by Axel Kohlmeyer, 2025-05-22