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Rowan

Rowan Python API

The rowan package is the official Python client for the Rowan computational chemistry platform. Submit workflows, poll or stream results, and manage molecules, proteins, folders, and projects—all from plain Python.

Installation

pip install rowan-python

pixi add --pypi rowan-python

uv add rowan-python

Authentication

Create an API key on your account page, then either export it as an environment variable or set it directly on the module:

import os

os.environ["ROWAN_API_KEY"]  # picked up automatically, or...

import rowan

rowan.api_key = "rowan-sk..."

Working in a shared process?

Use rowan.api_credentials to scope a key to a single with block instead of setting it globally — handy for multi-tenant scripts or test suites.

Quickstart

This example runs a geometry optimization on isoprene and streams each optimization step as it completes:

quickstart.py
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import rowan

folder = rowan.get_folder("examples")  # (1)!

workflow = rowan.submit_basic_calculation_workflow(
    initial_molecule=rowan.Molecule.from_smiles("CC(=C)C=C"),
    preset="rapid_semiempirical",  # (2)!
    tasks=["optimize"],
    name="Isoprene Optimization",
    folder=folder,
)

print(f"View workflow at: https://labs.rowansci.com/calculation/{workflow.uuid}")

for result in workflow.stream_result(poll_interval=3):  # (3)!
    if result.calculation_uuid:
        mols = rowan.retrieve_calculation_molecules(result.calculation_uuid)
        print(f"  {len(mols)} opt steps, energy={mols[-1].get('energy') if mols else None}")

print(result)  # (4)!
  1. Folders are created on first use — no need to pre-create them in the UI.
  2. Presets bundle a method, basis set, and corrections into one named choice. See Basic Calculation for the full list and when to use each one.
  3. stream_result polls the API and yields an updated result after every optimization step, instead of blocking until the whole workflow finishes.
  4. The final yielded result is the completed workflow — same object you'd get from workflow.result after workflow.wait().

What's next

  • Workflows

    Every Rowan workflow's submit function, settings, and result type, grouped by molecular modeling, property prediction, protein–ligand, spectrometry, and cheminformatics.

    Browse workflows

  • Objects

    Molecule, Protein, Folder, Project, Workflow, Calculation, and the account/API-key types every workflow builds on.

    Browse objects