Public evidence

mechanical.statics.plane_centroid

Machine-checked verification for calculation version 1.0.0 · tier engine_tested

Open calculator API Capability Download JSON MCP Review policy

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Production attestation Embedded snapshot: unpublished · Build schema 1.0.0 ready · Semantic contract ✓ · Attestation report not published on origin · Live production status STALE (3 capabilities; 189 remain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:a0f3f0e03ada0699cd9c50725fe5859e11b0edd1dad8b9aa4a9ce820f9bf4e5d

Input schema sha256:eaff4f751255836d0e227831d915e2a5ffd21810362954efdb5e58ab2ea8829e · Output schema sha256:ba150d4057a041215efbbb0735d67852526bb0480a7942d7d7e812dd9f0cd4dc · 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: plane-centroid
Engine: plane-centroid
Engine build: 2026-09-23
Evidence core: 2026-09-23T06:51:38.777Z
Rendered: 2026-09-23T10:57:00.181Z
Last reviewed: —

Limitations

Plane areas with a known part centroid
Negative area is a hole
Total area must not be zero
Not moment of inertia, radius of gyration, 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 — Center of gravity and centroid
Supports: x̄ = Σ(A x)/ΣA and ȳ = Σ(A y)/ΣA for a composite plane area

Published checks

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

ID	Kind	Status	Detail
`golden-two-areas`	golden	pass	Expected area=4 · x_bar=2 · y_bar=0 · model=plane_centroid · Actual n=2 · model=plane_centroid · area=4 · x_bar=2 · y_bar=0 · solver=math.vector add · convention=x̄ = Σ(A x)/ΣA, ȳ = Σ(A y)/ΣA. Negative area is a hole.
`golden-hole`	golden	pass	Expected area=2 · x_bar=-3 · y_bar=0 · Actual n=2 · model=plane_centroid · area=2 · x_bar=-3 · y_bar=0 · solver=math.vector add · convention=x̄ = Σ(A x)/ΣA, ȳ = Σ(A y)/ΣA. Negative area is a hole.
`boundary-single`	boundary	pass	Expected area=6 · x_bar=1 · y_bar=2 · Actual n=1 · model=plane_centroid · area=6 · x_bar=1 · y_bar=2 · solver=math.vector add · convention=x̄ = Σ(A x)/ΣA, ȳ = Σ(A y)/ΣA. Negative area is a hole.
`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