README.md

qcparse

A library for parsing Quantum Chemistry output files into structured data objects and converting structured input objects into program-native input files. Uses data structures from qcio.

qcparse works in harmony with a suite of other quantum chemistry tools for fast, structured, and interoperable quantum chemistry.

The QC Suite of Programs

• qcio - Beautiful and user friendly data structures for quantum chemistry.
• qcparse - A library for efficient parsing of quantum chemistry data into structured qcio objects and conversion of qcio input objects to program-native input files.
• qcop - A package for operating quantum chemistry programs using qcio standardized data structures. Compatible with TeraChem, psi4, QChem, NWChem, ORCA, Molpro, geomeTRIC and many more.
• BigChem - A distributed application for running quantum chemistry calculations at scale across clusters of computers or the cloud. Bring multi-node scaling to your favorite quantum chemistry program.
• ChemCloud - A web application and associated Python client for exposing a BigChem cluster securely over the internet.

✨ Basic Usage

• Installation:

  python -m pip install qcparse

• Parse a file into a SinglePointResults object with a single line of code.

  from qcparse import parse
  # May pass a path or the contents of a file as string/bytes
  results = parse("terachem", "/path/to/stdout.log")

• The results object will be a qcio.SinglePointResults object. Run dir(results) inside a Python interpreter to see the various values you can access. A few prominent values are shown here as an example:

  from qcparse import parse
  
  results = parse("/path/to/tc.out", "terachem")
  
  results.energy
  results.gradient # If a gradient calc
  results.hessian # If a hessian calc
  
  results.calcinfo_nmo # Number of molecular orbitals

• Parsed values can be written to disk like this:

  with open("results.json", "w") as f:
      f.write(result.model_dumps_json())

• And read from disk like this:

  from qcio import SinglePointResults
  
  results = SinglePointResults.open("results.json")

• You can also run qcparse from the command line like this:

  qcparse -h # Get help message for cli
  
  qcparse terachem ./path/to/tc.out > results.json # Parse TeraChem stdout to json

💻 Contributing

Please see the contributing guide for details on how to contribute new parsers to this project :)

If there's data you'd like parsed from output files or want to support input files for a new program, please open an issue in this repo explaining the data items you'd like parsed and include an example output file containing the data, like this.