CIFT

Caltech Intermediate Form parser in pure Python

• github: https://github.com/maybeetree/cift
• pypi: https://pypi.org/project/cift/0.0.1/

Under construction

Currently, CIFT is a utility for use in unit tests of RAIMAD, a different project I am working on. As such, it is only guaranteed to support CIF files that RAIMAD produces, and not all CIF files in general.

Turning CIFT into a general-purpose CIF parser is a long-term future goal.

Roadmap

• Complete this roadmap
• Parsing Variants
  • Strict (according to ¹ ) parsing
  • Klayout-like parsing
    • "lenient" layer names working, unclear whether this corresponds 1:1 with kalyout
• Basic parsing
  • P (polygons)
  • B (box)
    • rotation
  • Comments
    • Maybe? Untested
  • Subroutines (DS and DF)
  • Translation and rotation (subroutines)
• Inspection
  • Get CIF file as a list of geometries on each layer
  • Get CIF file as a tree representing subroutine calls

Overall Goals

• Pure Python, no dependencies
• easy to understand code
• mypy --strict has no complaints

Contributing

If you'd like to contribute code, please do so by making a fork, comitting your changes, and creating a pull request.

We have unit tests. Run them with python -m unittest from the root of the repo.

Name

• "CIFT", pronounced like "sift". Think of putting a CIF file into a sieve and letting the syntax crystallize into grains of sand that fall away to reveal the geometries it represents.

License

cift is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General Public License as published by the Free Software Foundation, version 3 of the License only.

cift is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more details.

You should have received a copy of the GNU Affero General Public License along with cift. If not, see https://www.gnu.org/licenses/.

Note: Previous versions of cift were released under different licenses. If the current license does not meet your needs, you may consider using an earlier version under the terms of its original license. You can find these versions by browsing the commit history.

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Copyright (c) 2025, maybetree.

Works Cited

Footnotes

1. Sproull, R., & Lyon, R. (1980). The caltech intermediate form for LSI layout description (Technical Report No. 2686). California Institute of Technology, Computer Science Department, Silicon Structures Project. ↩