Verification
5/5 calculation tests · Production surface contract 1/1
- Golden tests 0 / 0
- Boundary tests 0 / 0
- Property tests 5 / 5
- Production surface contract 1 / 1
}
- 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- Production attestation Embedded snapshot: unpublished · Build schema 1.0.0 ready · Semantic contract ✓ · Attestation report not published on origin · Live production status PASS (0 stale; 164 CURRENT) @ 2026-09-18T21:41:56.329Z
- Semantic contract PASS
- Evidence attested at 2026-09-18T21:41:55.460Z
- Last production check 2026-09-18T21:41:55.460Z
- Public / cache —
- Origin —
- Supplemental domain review Not performed
- Named expert review Not performed
- release artifacts aligned PASS
Fingerprint sha256:ecc3bbde0925ca03a090f48ccb8af01cbffcc7de78202b6a723c5b667a429807
Input schema sha256:6d642655fef31789a1ab59c2e485f2494803b52a1c93cf054c601f5429d47484 · Output schema sha256:e5f9db4ab8188483c4087cade377b3e0bc4d1ced90a53255e2d790de2ff6a577 · 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.
Engine identity and declared limitations.
- Tool
- trapezoidal-alternate-depth
- Engine
- trapezoidal-alternate-depth
- Engine build
- 2026-09-18
- Evidence core
- 2026-09-18T22:50:29.016Z
- Rendered
- 2026-09-18T23:14:09.774Z
- Last reviewed
- —
Assumptions
- Trapezoid alternate depths: E = y + Q²/(2g A²) with A=(b+z y)y; both y_sub>yc and y_super<yc at the same E, Q, b, z; SI; default g=9.80665; z>0 is run/rise
- Unknown is the pair (depths mode) or E (energy invert from one y); E>Ec=yc+D_c/2; Fr is reported not an input
- Not rectangular alternate depth; not trapezoid E from y+Q; not trapezoid yc as the product; not trapezoid yn; not Manning n; not Q=Av
Limitations
- Trapezoid alternate depths: E = y + Q²/(2g A²) with A=(b+z y)y; both y_sub>yc and y_super<yc at the same E, Q, b, z; SI; default g=9.80665; z>0 is run/rise
- Unknown is the pair (depths mode) or E (energy invert from one y); E>Ec=yc+D_c/2; Fr is reported not an input
- Not rectangular alternate depth; not trapezoid E from y+Q; not trapezoid yc as the product; not trapezoid yn; not Manning n; not Q=Av
Sources
Standards and references supporting this tool specification. Methods are listed separately — they are algorithms, not bibliographic sources.
- ISO 80000-4 — Mechanics — Energy and volume flow
Supports: E and y are lengths; Q is volume flow
- Chow, V.T. Open-Channel Hydraulics — Specific energy and alternate depths in a trapezoidal section
Supports: The same E gives two depths when E>Ec. Rectangular both y from E, Q, b is a different product. Trapezoid E from y and Q is a different product.
Published checks
Golden, boundary, and property cases included in this evidence build.
| ID | Kind | Status | Detail |
|---|
property-tad-ysub | property | pass | y_sub from E,Q,b,z |
property-tad-ysuper | property | pass | y_super<yc<y_sub |
property-tad-not-rect | property | pass | y_super≠rectangular pair |
property-tad-roundtrip-E | property | pass | E roundtrip |
property-tad-model | property | pass | alternate_depth_trapezoid |
