The httk₂ tutorial

This tutorial showcases the current modular httk₂ APIs through a sequence of short, practical examples.

The examples use the same vocabulary as the reference documentation, with deeper details linked from each page.

Install the pieces used by the tutorial

The httk2 metapackage installs the core, I/O, atomistic, analysis, and workflow modules. Database examples additionally need httk-store’s SQL extra; ASE is used only for the two visualization/interchange steps.

python -m pip install httk2 "httk-store[db]" ase

Feature map

Step	Tutorial feature	Current route	Main module
1	Load and inspect a structure	One-call loading and exact inspection	httk-atomistic
2	Build a structure in code	Native unit-cell construction	httk-atomistic
3	Visualize a structure	ASE interchange; no built-in viewer	httk-atomistic
4	Convert to/from ASE	Structure and ASE views	httk-atomistic
5	Build general, orthogonal, and cubic supercells	Exact supercell operations	httk-atomistic
6	Store structure data in SQLite	Representation-specific Records in SQL or MongoDB stores	httk-store
7	Search the local database	Backend-neutral query API	httk-store
8	Prepare a VASP calculation	Packaged templates and POSCAR preparation	httk-workflow
9	Generate a batch	Instantiation parameters and campaign partitioning	httk-workflow
10	Send and run remotely	Remote adapters, precheck, and runner builds	httk-workflow
11	Read results into the database	Workflow collection or explicit record storage	httk-workflow + httk-store
12	Draw a phase diagram	Composition and convex-hull analysis	httk-analyse
13	Store custom data	Frozen dataclasses	httk-store
14	Publish a project centrally	Signed local manifests; no central publisher	httk-workflow
15	Query an OPTIMADE server	Generic OPTIMADE client and structure loading	httk-serve

• 1. Load and inspect a structure
• 2. Build a structure in code
• 3. Visualize a structure
• 4. Build with ASE and convert to httk₂
• 5. Build supercells
• 6. Store data in SQLite
• 7. Search the local database
• 8. Prepare a VASP calculation
• 9. Create a Ca–Ti–O batch
• 10. Run the batch
• 11. Collect the results
• 12. Draw the Ca–Ti–O phase diagram
• 13. Store custom data
• 14. Publish a dataset or project
• 15. Query an OPTIMADE server