Home Developers Evidence math.exponential_growth

Public evidence

math.exponential_growth

Machine-checked verification for calculation version 1.0.7 · tier engine_tested

CVP: CVP VERIFIED · CVP protocol 1.0.0-proposed · Engineering assurance· periodic r > −100%; continuous uses k=ratePct; inverse solves any missing field among x₀, r, t given x(t) · Protocol · Schema · Production report

Declared partition coverage
PASS · 7/7 declared partitions (forward-periodic, forward-continuous, inverse-time, inverse-x0, inverse-rate, verify, invalid-domain)
Versions
Calculation 1.0.7 · CVP protocol 1.0.0-proposed
CVP identity
3/3 property · digest 4da3d88a831d

Verification

Legacy regression suite: 20/20 calculation tests · Production surface contract 27/27

Three distinct suites: educational examples on the calculator page, this legacy regression count (20/20 golden + boundary), and the CVP verification suite below. They are not the same number. Property, metamorphic, round-trip, O3, and interface statuses/checks are recorded in the CVP Manifest . SKIP (0/0) means that suite has no published vectors.

    This calculator CURRENT · Public schema 1.0.7 matches · Semantic contract ✓ · Production attested · Public/cache ✓ · Origin ✓

CVP verification suite

Protocol checks from the Evidence Manifest. Distinct from the legacy regression suite above. Calculation version 1.0.7. CVP 1.0.0-proposed. 5/5 golden · 6/6 CVP boundary · 6/6 invalid · 3/3 property · 1/1 metamorphic · 3/3 round-trip · 13/13 O3 · 1/1 cross-interface · 4/4 URL→result→graph · 24/24 CVP contract. digest 4da3d88a831d.

  • Golden (oracle-backed) 5 / 5
  • CVP boundary 6 / 6
  • Invalid input 6 / 6
  • Property 3 / 3
  • Metamorphic 1 / 1
  • Round-trip 3 / 3
  • O3 high-precision 13 / 13
  • Cross-interface 1 / 1
  • URL → result → graph 4 / 4
  • CVP contract 24 / 24
  • Interfaces PASS · UI (SSR) / REST / MCP / URL→result→graph
  • Interface claim Success 1/1. Integration: URL → SSR result → Live graph current point (4/4). Hydration/slider/history are URL-canonical contracts, not a live browser session.
  • Assurance Engineering
  • release artifacts aligned PASS
  • schema valid input executes PASS
  • engine success output validates schema PASS
  • schema rejects incomplete input PASS
  • input schema declares xt PASS
  • input schema accepts inverse time PASS
  • input schema accepts verify PASS
  • input schema rejects two fields PASS
  • output schema defines consistency PASS
  • input schema forward PASS
  • rest forward output schema PASS
  • rest forward consistency PASS
  • input schema forward continuous PASS
  • rest forward continuous output schema PASS
  • rest forward continuous consistency PASS
  • input schema inverse time PASS
  • rest inverse time output schema PASS
  • rest inverse time consistency PASS
  • input schema inverse x0 PASS
  • rest inverse x0 output schema PASS
  • rest inverse x0 consistency PASS
  • input schema inverse rate PASS
  • rest inverse rate output schema PASS
  • rest inverse rate consistency PASS
  • input schema verify PASS
  • rest verify output schema PASS
  • rest verify consistency PASS

Fingerprint sha256:db1f1770a512fc80cc710f57cdb3bb6c1ff47cf809b3c9b304d0a686c2a0e6dc

Input schema sha256:e17eaac04aa18c70f8036d533840884fb246b830e44fed4f23a1c3220871de2f · Output schema sha256:8ada2568a635f6d90dadd0b29de56555ba0063983c2886847b1959f3957c80bd · 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
exponential-growth
Engine
exponential-growth
Engine build
2026-09-10
Evidence core
2026-09-10T22:48:17.762Z
Rendered
2026-09-16T22:03:43.783Z
Last reviewed

Assumptions

  • Constant rate over the interval (real populations often need logistic models long-term).
  • CalculatorX defines the periodic model domain as r > −100% so the growth factor stays positive and inverse/logarithmic solving remains well-defined.

Limitations

  • Periodic model requires r > −100% → RATE_MUST_BE_GT_MINUS_100
  • Non-finite inputs → INVALID_NUMBER

Sources

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

Legacy published checks

Golden and boundary cases from the legacy Evidence JSON. CVP property, metamorphic, round-trip, O3, and interface statuses/checks are recorded in the Manifest — including SKIP when a suite has no vectors.

IDKindStatusDetail
pop-90goldenpassExpected 1705.9666670848055 · Actual 1705.9666670848055
11yrgoldenpassExpected 17103.39358116314 · Actual 17103.39358116314
solve-tgoldenpassExpected 22.51708530541102 · Actual 22.51708530541102
decay-10goldenpassExpected 34.86784401000001 · Actual 34.86784401000001
negative-tgoldenpassExpected 61.39132535407591 · Actual 61.39132535407591
zero-x0goldenpassExpected 0 · Actual 0
continuous-kgoldenpassExpected 74.59123488206352 · Actual 74.59123488206352
continuous-k-neggoldenpassExpected 33.51600230178197 · Actual 33.51600230178197
double-100pctgoldenpassExpected 32 · Actual 32
half-life-50pctgoldenpassExpected 1 · Actual 1
solve-x0goldenpassExpected 16 · Actual 16
solve-rategoldenpassExpected 100 · Actual 100
verify-pop90goldenpassExpected 1705.9666670848055 · Actual 1705.9666670848055
verify-display-mismatchgoldenpassExpected value=1705.9666670848055 · Actual value=1705.9666670848055
r-minus-100boundarypassExpected RATE_MUST_BE_GT_MINUS_100 · Actual RATE_MUST_BE_GT_MINUS_100
r-below-minus-100boundarypassExpected RATE_MUST_BE_GT_MINUS_100 · Actual RATE_MUST_BE_GT_MINUS_100
solve-t-nonpositiveboundarypassExpected INVALID_INPUT · Actual INVALID_INPUT
solve-t-zero-rateboundarypassExpected INVALID_INPUT · Actual INVALID_INPUT
solve-rate-zero-tboundarypassExpected INVALID_INPUT · Actual INVALID_INPUT
boundary-eg-rateboundarypassExpected RATE_MUST_BE_GT_MINUS_100 · Actual RATE_MUST_BE_GT_MINUS_100