Public evidence

mechanical.statics.principal_moment

Machine-checked verification for calculation version 1.0.0 · tier engine_tested

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Verification

6/6 calculation tests · Production surface contract 6/6

Golden tests 2 / 2
Boundary tests 4 / 4
Property tests 0 / 0
Production surface contract 6 / 6
Engine tested Yes
Source checked Yes
Artifact integrity PASS
Production attestation Embedded snapshot: unpublished · Build schema 1.0.0 ready · Semantic contract ✓ · Attestation report not published on origin · Live production status STALE (3 capabilities; 189 remain CURRENT) @ 2026-09-23T10:40:38.140Z
Semantic contract PASS
Evidence attested at 2026-09-23T02:27:54.588Z
Last production check 2026-09-23T02:27:54.588Z
Public / cache —
Origin —
Supplemental domain review Not performed
Named expert review Not performed

release artifacts aligned PASS
schema output required declared PASS
schema valid input executes PASS
engine success output validates schema PASS
schema rejects incomplete input PASS
rest success payload validates schema PASS

Fingerprint sha256:6fc7f10379b03566e635c32dfa70a8a08a25e2034b5beac8441ea3e5a31439aa

Input schema sha256:3e0599cac178918111b270ae1b6c8cb71e8211e0099e712f55617138e139c1fc · Output schema sha256:8306a15b09b7e2e8694cbb307977921dd060e079425ac0de8e80278bb971b73d · Build-time SHA-256 digests prove published artifacts agree with each other (release_integrity.scope=workspace). Production attestation GETs canonical URLs twice (public/cached view and origin), including Capability HTML, via npm run attest:production --write (published at /.well-known/calculatorx-production-attestation.json) and fails if the public Capability page advertises a different calculation_version. This is artifact consistency, not an independent immutable release log.

Build & scope

Engine identity and declared limitations.

Tool: principal-moment
Engine: principal-moment
Engine build: 2026-09-23
Evidence core: 2026-09-23T07:51:27.049Z
Rendered: 2026-09-23T10:57:00.182Z
Last reviewed: —

Limitations

Moments are supplied about each part centroid
θ is the I1 axis, CCW from +x, in (−90°, 90°]
Equal principal moments report θ = 0
Negative area is a hole
Total area must not be zero
Not a Mohr circle drawing, section modulus, or beam deflection

Sources

Standards and references supporting this tool specification. Methods are listed separately — they are algorithms, not bibliographic sources.

Hibbeler, Engineering Mechanics: Statics — Product of inertia and principal moments
Supports: Ixy = Īxy + A x' y' and the principal values of the plane inertia tensor

Published checks

Golden, boundary, and property cases included in this evidence build.

ID	Kind	Status	Detail
`golden-aligned`	golden	pass	Expected Ix=4 · Iy=1 · Ixy=0 · I1=4 · I2=1 · theta_deg=0 · model=principal_moment · Actual n=1 · model=principal_moment · area=2 · x_bar=0 · y_bar=0 · Ix=4 · Iy=1 · Ixy=0
`golden-shift`	golden	pass	Expected area=2 · x_bar=1 · y_bar=1 · Ix=2 · Iy=2 · Ixy=2 · I1=4 · I2=0 · Actual n=2 · model=principal_moment · area=2 · x_bar=1 · y_bar=1 · Ix=2 · Iy=2 · Ixy=2
`boundary-swap`	boundary	pass	Expected I1=4 · I2=1 · theta_deg=90 · Actual n=1 · model=principal_moment · area=2 · x_bar=0 · y_bar=0 · Ix=1 · Iy=4 · Ixy=0
`boundary-empty`	boundary	pass	Expected MISSING_REQUIRED_INPUT · Actual MISSING_REQUIRED_INPUT
`boundary-row`	boundary	pass	Expected INVALID_INPUT · Actual INVALID_INPUT
`boundary-cancel`	boundary	pass	Expected INVALID_INPUT · Actual INVALID_INPUT