FESADev/docs/hex8-structural-analysis/verification.md

Hex8 original comparison evidence

This page records T8's comparison-only Python implementation and its observed results. It does not replace the feature PRD, numerical controls or completion checklist. The comparator reads official rounded Float64 quantities; it does not recompute the internal high+low solver acceptance gates from those observables.

Entry point and identities

uv run --with h5py --with pytest python scripts/verification/compare_hex8.py requires --case, the actual scratch --input, official --results, and --report. --references defaults to reference/hexa. The optional --execution-record consumes a closed native CLI record; it never executes its command. A supplied record must have native exit0, unchanged original/copy byte identities, and the exact input and result hashes. Without that record the report explicitly certifies file comparison only, not successful solver execution.

For example, after a real original run has naturally completed:

uv run --with h5py --with pytest python scripts/verification/compare_hex8.py `
  --case hexa_linearstatic --input <scratch>/hexa_linearstatic.inp `
  --results <scratch>/hexa_linearstatic_results.h5 `
  --execution-record <scratch>/native.json --report <evidence>/comparison.json

The report path may not overwrite an input, reference, execution record or result. Authoritative repository originals remain protected even with alternate copied references; existing symlink/junction and hardlink aliases are also checked. Exit0 means the declared comparison passes; exit1 means a numerical family fails; exit2 means an identity/schema/finite/precondition error or missing modal reference. The tool is not a solver launcher, result generator, reference repair or release readiness check.

The fixed source inventory is the reference-model inventory: 442 nodes, 300 C3D8 elements and 13 frozen original files. Input and CSV raw SHA256 must match the documented Windows working-tree bytes. The HDF5 metadata must identify the actual lexically normalized absolute scratch path and that file's FNV1a64 content identity; a different path with identical bytes is not silently accepted.

Complete CSV identities are checked before any physical values are converted. Complete required Solid model/frame/physical schemas, UTF-8 attributes and explicit LE F64/U64/U8 widths are then checked. Result arrays join the source node or source element/point labels through their internal ID maps; CSV row order is not an identity. Physical values, including nonprojected RF rows and unused exported CSV derived quantities, must be finite before tolerance evaluation.

Static reference increment10 maps to the completed load-factor1 frame, independent of its HDF5 storage frame index. RF validates all442 source rows before projecting the actual51 constrained scalar components. It never compares free RF with free residual. Stress compares all300×8×6 unaveraged global Cauchy components. Fixed IntPt1–8 conventions are checked without nearest-coordinate remapping. Point coordinates are auxiliary: CSV coordinate errors use the approved 16*float32-eps*sum(abs(Na*Xa_axis)) source-resolution budget; the scalar stress policy is unchanged.

Dynamic comparisons require exactly101 accepted frames. Integer increment0–100 is matched first, source decimal time must equal n/10, and each stored time must be binary64 n*0.1. Each frame's1326 U scalars form a separate blocking family. There is no interpolation, nearest-time matching, scale sharing between frames, rotation family or acceleration/energy reference claim.

Common numerical policy

Every static case has independent U-global, constrained RF-global and S-global blocking families. Every dynamic frame has its own U-global blocking family. For each family, only reference values define S=max(abs(reference)) and B=.01S. Rows with abs(reference)<=B require absolute error<=B; other rows require relative error<=.05. All-row RMS/S must also be<=.01. Boundaries are inclusive, and S=0 requires every actual value to be exactly0. No absolute floor, denominator clamp, row deletion or cancellation of signed errors is applied. Reports preserve each scalar identity/value/error/branch/pass and family scale/band/max-absolute-error, absolute/relative RMS, source SHA and policy.

The independent typed modal comparison behavior requires explicit source step, mode1–10, eigenvalue or frequency quantity, and matching 1/time^2 or 1/time units. Each mode is a singleton using the same RMS1% policy. This is not an assumption about the absent original Value file's eventual CSV layout. Actual modal original comparison remains NOT RUN until a genuine reference is provided and its semantics and hashes are confirmed.

Current observations

The initial seven behavior assertions failed before implementation (pytest native exit1). The first expanded suite passed63/63 with native exit0. Those tests include original-sized independently declared HDF5 schema fixtures and reference values; they are comparator behavior fixtures, not actual FESA source validation evidence. The affected Hex8 plus legacy HHT comparator suite passed119/119 (native exit0, 62.51s) before independent review fixes. Those bounded fixes were reproduced by safe behavior RED tests and the five targeted regressions then passed5/5. Final affected checks after all three independent findings were corrected passed 124/124 with native exit0 (81.41s), with raw stdout and JUnit retained under .harness/hex8-evidence/t8/final-affected/. The preliminary whole uv ... pytest -q attempt and the separate exact configured uv run --with h5py --with pytest python -B -m pytest -v -rs (docs/operations.md:87, adding h5py) both stopped during collection with native exit2 and five legacy operational import errors (msvc_harness and removed scripts.hooks). It is not a whole-suite PASS; no tests were excluded and no retired orchestration was restored.

Actual official linear-static and nonlinear-static results passed source, model, schema, point, finite and frame prechecks and failed all three numerical families. Their closed CLI evidence records both have native exit0 and matching original/copy/result hashes; their comparator commands have native exit1. These are genuine comparison failures under the unchanged policy, not reader precheck failures or solver native execution failures. Frequency official readback passes its prechecks; its comparator exits2 with not-run, not PASS.

Case / blocking quantity	Scalars	Failing rows	S	Maximum absolute error	RMS/S
linear static U	1326	79	.00186131289	.00007588175038730229	.016739519723527385
linear static RF	51	34	513497.094	78630.61640144575	.06818892528188494
linear static S	14400	7783	3430145	982855.3871926877	.04270903417463437
nonlinear static U	1326	79	.00186110672	.00007586510202476195	.016737790679783753
nonlinear static RF	51	34	513445.594	78623.61011241788	.0681899286018377
nonlinear static S	14400	7782	3429817.75	982753.151651503	.04270850513087158

Official result SHA256 values are 3ef92c35ea83ddb4d11437ff87ef15eca7dac179d378eda19570abae579b09d0 (linear), 0095ebf2d360a8bd8a71212af0dd500ed611a56540a173a39d9c8d88d8e05bbf (nonlinear), and 0ec4d2b09250bab17a8532228cd34a312518c04023076f971e929b387031c6b3 (frequency). Scratch inputs are retained under .harness/hex8-evidence/t8-original-cli/<case>/<case>.inp. Root preserved each exact command, closed native exit and full row report under .harness/hex8-evidence/t8-comparator-frozen/official-comparisons/<case>/. The command records identify the actual scratch input, original reference directory, HDF5 and closed native CLI record consumed. The frozen author revision 0b93c0c59cf64db44003ebe5217a4efb8307a8ba passed independent bounded review and was integrated as 317fe5c. Root and reviewer separately verified four owned source blobs/snapshots, 65 closed raw artifacts and all13 unchanged source hashes. The raw affected stdout/JUnit certifies124 tests (Hex8 83, legacy HHT 41), zero failures/errors/skips and native0. This review certifies the comparator behavior and evidence, not numerical agreement with the originals. Naturally completed dynamic originals and whole-feature validation are tracked separately.

After integration, the root affected suite also passed124/124 with native0 (70.92s). Root comparison-only commands consumed the same naturally closed official results and again returned static native1 with the same failed family metrics and frequency native2 (not-run). These commands and raw stdout/JUnit/row reports are retained under .harness/hex8-evidence/t8-integrated/. No original solver case was rerun to perform these comparisons.

Actual original	Current comparison state
hexa_linearstatic	Full precheck PASS; U/RF/S numerical FAIL (comparator native1)
hexa_nonlinearstatic	Full precheck PASS; U/RF/S numerical FAIL (comparator native1)
hexa_dynlinear	NOT RUN by comparator; root-owned actual CLI run pending
hexa_dynnonlinear	NOT RUN by comparator; root-owned actual CLI run pending
hexa_freq	Official HDF5 precheck PASS; modal Value absent, actual comparison NOT RUN (native2)

Full MSVC build/CTest, original CLI orchestration, independent numerical/physics investigation of the reference conflict and whole-feature completion are root-owned and are not inferred from this Python implementation or its fixture tests.