FESADev/phases/1-linear-static-mitc4-rebaseline/step5.md

Sprint Contract: Dof Manager Reaction Foundation

Objective

Rebuild or verify the six-DOF DofManager, constrained/free mapping, equation numbering, sparse-pattern inputs, and full-vector reconstruction needed for reaction recovery.

Required Reading

• /AGENTS.md
• /docs/ARCHITECTURE.md
• /docs/ADR.md
• /docs/NUMERICAL_CONVENTIONS.md
• /docs/RESULTS_SCHEMA.md

Scope

• Manage active six-DOF shell nodes.
• Apply fixed constraints by constrained DOF elimination.
• Own equation numbering and sparse connectivity inputs.
• Reconstruct full vectors in original global DOF order.
• Provide data needed for RF = K_full * U_full - F_full.

Allowed Files

• include/
• src/
• tests/
• PLAN.md
• PROGRESS.md

Explicit Non-Goals

• Do not assemble MITC4 stiffness.
• Do not store equation ids in Node or Element.
• Do not compute RF from reduced vectors only.

Tests To Write First

• DOF activation and Abaqus component order.
• Constrained/free partition tests.
• Equation numbering stability with noncontiguous node ids.
• Full/reduced vector reconstruction tests.
• Sparse-pattern connectivity input tests.
• Full-vector reaction formula unit test with a small known matrix.

Reference Artifacts

• None.

Acceptance Commands

python scripts/validate_workspace.py

Evaluator Checklist

• DofManager owns all equation numbering.
• Full-space order is deterministic and matches UX,UY,UZ,RX,RY,RZ.
• Reaction foundation preserves constrained DOF information.

Handoff Requirements

• Record DOF and reaction foundation status in PROGRESS.md.

Do Not

• Do not bypass DofManager from elements or analysis code.