Kind Request for Assistance: HEC-HMS API Documentation

[sunzichuan]

Dear Mr. Katzenmeyer

I hope this email finds you well.

I am currently working on automating HEC-HMS using Python and have studied your HEC-Commander code, which has been incredibly helpful for my work. However, I’m now trying to achieve a more specific task: inputting forecasted precipitation data and outputting discharge data using pre-calibrated parameters.

While I understand the basics, I’m unsure which API interfaces to use for this purpose or how to properly implement them. Would you be able to provide guidance on the relevant API calls needed for this functionality? Any advice or examples you could share would be greatly appreciated.

Thank you in advance for your time and expertise—your work has already been invaluable to my project, and I’d be truly grateful for your continued support.

Looking forward to your insights.

Best regards,

[gpt-cmdr]

I apologize, I kept looking for this issue on the ras-commander library - it may be more appropriate there: https://github.com/gpt-cmdr/ras-commander

I do not currently have built-in support for inputting forecasted precipitation data. I assume you are using DSS files with spatially varying precipitation grids? If so, updating the unsteady file can be done by utilizing the ras.runsteady_df which has a column with unsteady number and a column with the full_path of each unsteady file. That makes it simpler to perform programmatic changes to those files. I would suggest feeding in this example: https://github.com/gpt-cmdr/ras-commander/blob/main/examples/03_unsteady_flow_operations.ipynb and providing an example of how you want the unsteady file to be edited to point to your updated DSS File and/or DSS Path, and ask for a notebook/script that will handle the creation of new plans and unsteady files, and creating the run sets based on your current DSS file naming conventions.

Similarly, I do not have a direct method for calculating discharge across 2D cells, although this example notebook
https://github.com/gpt-cmdr/ras-commander/blob/main/examples/13_2d_detail_face_data_extraction.ipynb
does have that logic included implicitly. You should be able to feed that example notebook as well as the HDF Function knowledge base
https://github.com/gpt-cmdr/ras-commander/blob/main/ai_tools/llm_knowledge_bases/ras_commander_hdf_functions_only.txt into an LLM and ask for a function that will calculate discharge for a given polyline, and check it against RASMapper. That would allow you to define a location and extract the discharge there programmatically for each plan, and incorporate that into your sensitivity or calibration/validation.

If you get either of these functions running and tested, I would be happy to include them in the library with an example notebook!