FAILURE MAP
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FA-69086 / Tide and marine navigation tables / Open access

Tidal height window: Window edges are rounded to the nearest minute · case 01

Published windows can open before the water is deep enough.

Verified by executionVariant 1 · 7 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

Both window edges use round-half-up instead of rounding the start up and the end down.

THE FAILURE

Both window edges use round-half-up instead of rounding the start up and the end down.

Unsuccessful approach: Rounding the opening down and the closing up widens the window in the unsafe direction.

Case contract

Input [ts, hs, req]: sample times (minutes) and heights. Return the list of [start, end] intervals where height>=req, with crossing times linearly interpolated and rounded conservatively inward (start up, end down, 1e-9 tolerance); windows that vanish after rounding are dropped. A window open at the first sample starts at ts[0]; one still open at the end closes at ts[-1].

Why this case matters

Tide tables and passage plans turn published predictions into go/no-go decisions about depth, clearance and timing.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
import math
N = 1
observations = []
def solve(x):
    ts,hs,req=x
    wins=[]
    def close(a,b):
        s0,e0=math.floor(a+0.5),math.floor(b+0.5)
        if s0<=e0: wins.append([s0,e0])
    start=ts[0] if hs[0]>=req else None
    for k in range(1,len(ts)):
        a,b=hs[k-1],hs[k]
        if (a>=req)!=(b>=req):
            tc=ts[k-1]+(ts[k]-ts[k-1])*(req-a)/(b-a)
            if b>=req: start=tc
            else:
                if start is not None: close(start,tc)
                start=None
    if start is not None: close(start,ts[-1])
    return wins
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[('tidal height window [[0, 60, 120, 180, 240, 300, 360], [1.0, 1.8, 2.9, 3.6, 3.1, 2.2, 1.4], 2.5]', [[0, 60, 120, 180, 240, 300, 360], [1.0, 1.8, 2.9, 3.6, 3.1, 2.2, 1.4], 2.5], [[99, 280]]), ('tidal height window [[0, 60, 120, 180, 240, 300, 360], [1.0, 1.8, 2.9, 3.6, 3.1, 2.2, 1.4], 3.3]', [[0, 60, 120, 180, 240, 300, 360], [1.0, 1.8, 2.9, 3.6, 3.1, 2.2, 1.4], 3.3], [[155, 216]]), ('tidal height window [[0, 60, 120, 180, 240], [3.0, 2.6, 2.0, 2.4, 2.8], 2.5]', [[0, 60, 120, 180, 240], [3.0, 2.6, 2.0, 2.4, 2.8], 2.5], [[0, 70], [195, 240]]), ('tidal height window [[0, 60, 120, 180, 240], [2.5, 2.6, 2.0, 2.4, 2.8], 2.5]', [[0, 60, 120, 180, 240], [2.5, 2.6, 2.0, 2.4, 2.8], 2.5], [[0, 70], [195, 240]]), ('tidal height window [[0, 30, 60, 90, 120], [1.0, 2.0, 3.0, 2.0, 1.0], 2.0]', [[0, 30, 60, 90, 120], [1.0, 2.0, 3.0, 2.0, 1.0], 2.0], [[30, 90]]), ('tidal height window [[0, 45, 90, 135], [0.5, 0.7, 0.9, 0.6], 2.0]', [[0, 45, 90, 135], [0.5, 0.7, 0.9, 0.6], 2.0], []), ('tidal height window [[0, 60, 120], [2.1, 2.2, 2.3], 2.0]', [[0, 60, 120], [2.1, 2.2, 2.3], 2.0], [[0, 120]])], [('tidal height window [[0, 60, 120, 180, 240, 300, 360], [1.0, 1.8, 2.9, 3.6, 3.1, 2.2, 1.4], 3.3]', [[0, 60, 120, 180, 240, 300, 360], [1.0, 1.8, 2.9, 3.6, 3.1, 2.2, 1.4], 3.3], [[155, 216]]), ('tidal height window [[0, 60, 120, 180, 240], [2.5, 2.6, 2.0, 2.4, 2.8], 2.5]', [[0, 60, 120, 180, 240], [2.5, 2.6, 2.0, 2.4, 2.8], 2.5], [[0, 70], [195, 240]]), ('tidal height window [[0, 30, 60, 90, 120], [1.0, 2.0, 3.0, 2.0, 1.0], 2.0]', [[0, 30, 60, 90, 120], [1.0, 2.0, 3.0, 2.0, 1.0], 2.0], [[30, 90]]), ('tidal height window [[0, 45, 90, 135], [0.5, 0.7, 0.9, 0.6], 2.0]', [[0, 45, 90, 135], [0.5, 0.7, 0.9, 0.6], 2.0], []), ('tidal height window [[0, 60, 120], [2.1, 2.2, 2.3], 2.0]', [[0, 60, 120], [2.1, 2.2, 2.3], 2.0], [[0, 120]]), ('tidal height window [[0, 60, 120, 180, 240, 300], [0.8, 1.9, 2.6, 1.7, 2.4, 3.0], 2.2]', [[0, 60, 120, 180, 240, 300], [0.8, 1.9, 2.6, 1.7, 2.4, 3.0], 2.2], [[86, 146], [223, 300]]), ('tidal height window [[0, 50, 100, 150], [1.0, 2.0, 3.0, 1.0], 1.5]', [[0, 50, 100, 150], [1.0, 2.0, 3.0, 1.0], 1.5], [[25, 137]])], [('tidal height window [[0, 60, 120, 180, 240, 300], [0.8, 1.9, 2.6, 1.7, 2.4, 3.0], 2.2]', [[0, 60, 120, 180, 240, 300], [0.8, 1.9, 2.6, 1.7, 2.4, 3.0], 2.2], [[86, 146], [223, 300]]), ('tidal height window [[0, 60, 120], [2.1, 2.2, 2.3], 2.0]', [[0, 60, 120], [2.1, 2.2, 2.3], 2.0], [[0, 120]]), ('tidal height window [[0, 50, 100, 150], [1.0, 2.0, 3.0, 1.0], 1.5]', [[0, 50, 100, 150], [1.0, 2.0, 3.0, 1.0], 1.5], [[25, 137]]), ('tidal height window [[100, 160, 220, 280], [1.0, 1.3, 1.9, 2.2], 1.45]', [[100, 160, 220, 280], [1.0, 1.3, 1.9, 2.2], 1.45], [[175, 280]]), ('tidal height window [[0, 60, 120, 180], [3.0, 1.0, 1.0, 3.0], 1.5]', [[0, 60, 120, 180], [3.0, 1.0, 1.0, 3.0], 1.5], [[0, 45], [135, 180]]), ('tidal height window [[0, 60, 120, 180, 240], [1.0, 2.5, 1.0, 2.6, 1.0], 2.0]', [[0, 60, 120, 180, 240], [1.0, 2.5, 1.0, 2.6, 1.0], 2.0], [[40, 80], [158, 202]]), ('tidal height window [[0, 60, 120, 180, 240, 300, 360], [1.0, 1.8, 2.9, 3.6, 3.1, 2.2, 1.4], 2.5]', [[0, 60, 120, 180, 240, 300, 360], [1.0, 1.8, 2.9, 3.6, 3.1, 2.2, 1.4], 2.5], [[99, 280]])], [('tidal height window [[0, 50, 100, 150], [1.0, 2.0, 3.0, 1.0], 1.5]', [[0, 50, 100, 150], [1.0, 2.0, 3.0, 1.0], 1.5], [[25, 137]]), ('tidal height window [[100, 160, 220, 280], [1.0, 1.3, 1.9, 2.2], 1.45]', [[100, 160, 220, 280], [1.0, 1.3, 1.9, 2.2], 1.45], [[175, 280]]), ('tidal height window [[0, 60, 120, 180], [3.0, 1.0, 1.0, 3.0], 1.5]', [[0, 60, 120, 180], [3.0, 1.0, 1.0, 3.0], 1.5], [[0, 45], [135, 180]]), ('tidal height window [[0, 60, 120, 180, 240], [1.0, 2.5, 1.0, 2.6, 1.0], 2.0]', [[0, 60, 120, 180, 240], [1.0, 2.5, 1.0, 2.6, 1.0], 2.0], [[40, 80], [158, 202]]), ('tidal height window [[0, 60, 120, 180, 240, 300, 360], [1.0, 1.8, 2.9, 3.6, 3.1, 2.2, 1.4], 2.5]', [[0, 60, 120, 180, 240, 300, 360], [1.0, 1.8, 2.9, 3.6, 3.1, 2.2, 1.4], 2.5], [[99, 280]]), ('tidal height window [[0, 60, 120, 180, 240, 300, 360], [1.0, 1.8, 2.9, 3.6, 3.1, 2.2, 1.4], 3.3]', [[0, 60, 120, 180, 240, 300, 360], [1.0, 1.8, 2.9, 3.6, 3.1, 2.2, 1.4], 3.3], [[155, 216]]), ('tidal height window [[0, 60, 120, 180, 240], [3.0, 2.6, 2.0, 2.4, 2.8], 2.5]', [[0, 60, 120, 180, 240], [3.0, 2.6, 2.0, 2.4, 2.8], 2.5], [[0, 70], [195, 240]])], [('tidal height window [[0, 60, 120, 180, 240], [1.0, 2.5, 1.0, 2.6, 1.0], 2.0]', [[0, 60, 120, 180, 240], [1.0, 2.5, 1.0, 2.6, 1.0], 2.0], [[40, 80], [158, 202]]), ('tidal height window [[0, 60, 120, 180, 240, 300, 360], [1.0, 1.8, 2.9, 3.6, 3.1, 2.2, 1.4], 2.5]', [[0, 60, 120, 180, 240, 300, 360], [1.0, 1.8, 2.9, 3.6, 3.1, 2.2, 1.4], 2.5], [[99, 280]]), ('tidal height window [[0, 60, 120, 180, 240, 300, 360], [1.0, 1.8, 2.9, 3.6, 3.1, 2.2, 1.4], 3.3]', [[0, 60, 120, 180, 240, 300, 360], [1.0, 1.8, 2.9, 3.6, 3.1, 2.2, 1.4], 3.3], [[155, 216]]), ('tidal height window [[0, 60, 120, 180, 240], [3.0, 2.6, 2.0, 2.4, 2.8], 2.5]', [[0, 60, 120, 180, 240], [3.0, 2.6, 2.0, 2.4, 2.8], 2.5], [[0, 70], [195, 240]]), ('tidal height window [[0, 60, 120, 180, 240], [2.5, 2.6, 2.0, 2.4, 2.8], 2.5]', [[0, 60, 120, 180, 240], [2.5, 2.6, 2.0, 2.4, 2.8], 2.5], [[0, 70], [195, 240]]), ('tidal height window [[0, 30, 60, 90, 120], [1.0, 2.0, 3.0, 2.0, 1.0], 2.0]', [[0, 30, 60, 90, 120], [1.0, 2.0, 3.0, 2.0, 1.0], 2.0], [[30, 90]]), ('tidal height window [[0, 45, 90, 135], [0.5, 0.7, 0.9, 0.6], 2.0]', [[0, 45, 90, 135], [0.5, 0.7, 0.9, 0.6], 2.0], [])]]
for label, args, expected in fixtures[N-1]:
    check(label, solve(args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
tidal height window [[0, 60, 120, 180, 240, 300, 360], [1.0, 1.8, 2.9, 3.6, 3.1, 2.2, 1.4], 2.5][[98, 280]][[99, 280]]Failed
tidal height window [[0, 60, 120, 180, 240, 300, 360], [1.0, 1.8, 2.9, 3.6, 3.1, 2.2, 1.4], 3.3][[154, 216]][[155, 216]]Failed
tidal height window [[0, 60, 120, 180, 240], [3.0, 2.6, 2.0, 2.4, 2.8], 2.5][[0, 70], [195, 240]][[0, 70], [195, 240]]Passed
tidal height window [[0, 60, 120, 180, 240], [2.5, 2.6, 2.0, 2.4, 2.8], 2.5][[0, 70], [195, 240]][[0, 70], [195, 240]]Passed
tidal height window [[0, 30, 60, 90, 120], [1.0, 2.0, 3.0, 2.0, 1.0], 2.0][[30, 90]][[30, 90]]Passed
tidal height window [[0, 45, 90, 135], [0.5, 0.7, 0.9, 0.6], 2.0][][]Passed
tidal height window [[0, 60, 120], [2.1, 2.2, 2.3], 2.0][[0, 120]][[0, 120]]Passed

SHA-256 / 2ab3aaeda71f24a3719f07e13bc255093db1ffcc095b68cd96cfa1fd1ebad5ac

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
import math
N = 1
observations = []
def solve(x):
    ts,hs,req=x
    wins=[]
    def close(a,b):
        s0,e0=math.floor(a+1e-9),math.ceil(b-1e-9)
        if s0<=e0: wins.append([s0,e0])
    start=ts[0] if hs[0]>=req else None
    for k in range(1,len(ts)):
        a,b=hs[k-1],hs[k]
        if (a>=req)!=(b>=req):
            tc=ts[k-1]+(ts[k]-ts[k-1])*(req-a)/(b-a)
            if b>=req: start=tc
            else:
                if start is not None: close(start,tc)
                start=None
    if start is not None: close(start,ts[-1])
    return wins
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[('tidal height window [[0, 60, 120, 180, 240, 300, 360], [1.0, 1.8, 2.9, 3.6, 3.1, 2.2, 1.4], 2.5]', [[0, 60, 120, 180, 240, 300, 360], [1.0, 1.8, 2.9, 3.6, 3.1, 2.2, 1.4], 2.5], [[99, 280]]), ('tidal height window [[0, 60, 120, 180, 240, 300, 360], [1.0, 1.8, 2.9, 3.6, 3.1, 2.2, 1.4], 3.3]', [[0, 60, 120, 180, 240, 300, 360], [1.0, 1.8, 2.9, 3.6, 3.1, 2.2, 1.4], 3.3], [[155, 216]]), ('tidal height window [[0, 60, 120, 180, 240], [3.0, 2.6, 2.0, 2.4, 2.8], 2.5]', [[0, 60, 120, 180, 240], [3.0, 2.6, 2.0, 2.4, 2.8], 2.5], [[0, 70], [195, 240]]), ('tidal height window [[0, 60, 120, 180, 240], [2.5, 2.6, 2.0, 2.4, 2.8], 2.5]', [[0, 60, 120, 180, 240], [2.5, 2.6, 2.0, 2.4, 2.8], 2.5], [[0, 70], [195, 240]]), ('tidal height window [[0, 30, 60, 90, 120], [1.0, 2.0, 3.0, 2.0, 1.0], 2.0]', [[0, 30, 60, 90, 120], [1.0, 2.0, 3.0, 2.0, 1.0], 2.0], [[30, 90]]), ('tidal height window [[0, 45, 90, 135], [0.5, 0.7, 0.9, 0.6], 2.0]', [[0, 45, 90, 135], [0.5, 0.7, 0.9, 0.6], 2.0], []), ('tidal height window [[0, 60, 120], [2.1, 2.2, 2.3], 2.0]', [[0, 60, 120], [2.1, 2.2, 2.3], 2.0], [[0, 120]])], [('tidal height window [[0, 60, 120, 180, 240, 300, 360], [1.0, 1.8, 2.9, 3.6, 3.1, 2.2, 1.4], 3.3]', [[0, 60, 120, 180, 240, 300, 360], [1.0, 1.8, 2.9, 3.6, 3.1, 2.2, 1.4], 3.3], [[155, 216]]), ('tidal height window [[0, 60, 120, 180, 240], [2.5, 2.6, 2.0, 2.4, 2.8], 2.5]', [[0, 60, 120, 180, 240], [2.5, 2.6, 2.0, 2.4, 2.8], 2.5], [[0, 70], [195, 240]]), ('tidal height window [[0, 30, 60, 90, 120], [1.0, 2.0, 3.0, 2.0, 1.0], 2.0]', [[0, 30, 60, 90, 120], [1.0, 2.0, 3.0, 2.0, 1.0], 2.0], [[30, 90]]), ('tidal height window [[0, 45, 90, 135], [0.5, 0.7, 0.9, 0.6], 2.0]', [[0, 45, 90, 135], [0.5, 0.7, 0.9, 0.6], 2.0], []), ('tidal height window [[0, 60, 120], [2.1, 2.2, 2.3], 2.0]', [[0, 60, 120], [2.1, 2.2, 2.3], 2.0], [[0, 120]]), ('tidal height window [[0, 60, 120, 180, 240, 300], [0.8, 1.9, 2.6, 1.7, 2.4, 3.0], 2.2]', [[0, 60, 120, 180, 240, 300], [0.8, 1.9, 2.6, 1.7, 2.4, 3.0], 2.2], [[86, 146], [223, 300]]), ('tidal height window [[0, 50, 100, 150], [1.0, 2.0, 3.0, 1.0], 1.5]', [[0, 50, 100, 150], [1.0, 2.0, 3.0, 1.0], 1.5], [[25, 137]])], [('tidal height window [[0, 60, 120, 180, 240, 300], [0.8, 1.9, 2.6, 1.7, 2.4, 3.0], 2.2]', [[0, 60, 120, 180, 240, 300], [0.8, 1.9, 2.6, 1.7, 2.4, 3.0], 2.2], [[86, 146], [223, 300]]), ('tidal height window [[0, 60, 120], [2.1, 2.2, 2.3], 2.0]', [[0, 60, 120], [2.1, 2.2, 2.3], 2.0], [[0, 120]]), ('tidal height window [[0, 50, 100, 150], [1.0, 2.0, 3.0, 1.0], 1.5]', [[0, 50, 100, 150], [1.0, 2.0, 3.0, 1.0], 1.5], [[25, 137]]), ('tidal height window [[100, 160, 220, 280], [1.0, 1.3, 1.9, 2.2], 1.45]', [[100, 160, 220, 280], [1.0, 1.3, 1.9, 2.2], 1.45], [[175, 280]]), ('tidal height window [[0, 60, 120, 180], [3.0, 1.0, 1.0, 3.0], 1.5]', [[0, 60, 120, 180], [3.0, 1.0, 1.0, 3.0], 1.5], [[0, 45], [135, 180]]), ('tidal height window [[0, 60, 120, 180, 240], [1.0, 2.5, 1.0, 2.6, 1.0], 2.0]', [[0, 60, 120, 180, 240], [1.0, 2.5, 1.0, 2.6, 1.0], 2.0], [[40, 80], [158, 202]]), ('tidal height window [[0, 60, 120, 180, 240, 300, 360], [1.0, 1.8, 2.9, 3.6, 3.1, 2.2, 1.4], 2.5]', [[0, 60, 120, 180, 240, 300, 360], [1.0, 1.8, 2.9, 3.6, 3.1, 2.2, 1.4], 2.5], [[99, 280]])], [('tidal height window [[0, 50, 100, 150], [1.0, 2.0, 3.0, 1.0], 1.5]', [[0, 50, 100, 150], [1.0, 2.0, 3.0, 1.0], 1.5], [[25, 137]]), ('tidal height window [[100, 160, 220, 280], [1.0, 1.3, 1.9, 2.2], 1.45]', [[100, 160, 220, 280], [1.0, 1.3, 1.9, 2.2], 1.45], [[175, 280]]), ('tidal height window [[0, 60, 120, 180], [3.0, 1.0, 1.0, 3.0], 1.5]', [[0, 60, 120, 180], [3.0, 1.0, 1.0, 3.0], 1.5], [[0, 45], [135, 180]]), ('tidal height window [[0, 60, 120, 180, 240], [1.0, 2.5, 1.0, 2.6, 1.0], 2.0]', [[0, 60, 120, 180, 240], [1.0, 2.5, 1.0, 2.6, 1.0], 2.0], [[40, 80], [158, 202]]), ('tidal height window [[0, 60, 120, 180, 240, 300, 360], [1.0, 1.8, 2.9, 3.6, 3.1, 2.2, 1.4], 2.5]', [[0, 60, 120, 180, 240, 300, 360], [1.0, 1.8, 2.9, 3.6, 3.1, 2.2, 1.4], 2.5], [[99, 280]]), ('tidal height window [[0, 60, 120, 180, 240, 300, 360], [1.0, 1.8, 2.9, 3.6, 3.1, 2.2, 1.4], 3.3]', [[0, 60, 120, 180, 240, 300, 360], [1.0, 1.8, 2.9, 3.6, 3.1, 2.2, 1.4], 3.3], [[155, 216]]), ('tidal height window [[0, 60, 120, 180, 240], [3.0, 2.6, 2.0, 2.4, 2.8], 2.5]', [[0, 60, 120, 180, 240], [3.0, 2.6, 2.0, 2.4, 2.8], 2.5], [[0, 70], [195, 240]])], [('tidal height window [[0, 60, 120, 180, 240], [1.0, 2.5, 1.0, 2.6, 1.0], 2.0]', [[0, 60, 120, 180, 240], [1.0, 2.5, 1.0, 2.6, 1.0], 2.0], [[40, 80], [158, 202]]), ('tidal height window [[0, 60, 120, 180, 240, 300, 360], [1.0, 1.8, 2.9, 3.6, 3.1, 2.2, 1.4], 2.5]', [[0, 60, 120, 180, 240, 300, 360], [1.0, 1.8, 2.9, 3.6, 3.1, 2.2, 1.4], 2.5], [[99, 280]]), ('tidal height window [[0, 60, 120, 180, 240, 300, 360], [1.0, 1.8, 2.9, 3.6, 3.1, 2.2, 1.4], 3.3]', [[0, 60, 120, 180, 240, 300, 360], [1.0, 1.8, 2.9, 3.6, 3.1, 2.2, 1.4], 3.3], [[155, 216]]), ('tidal height window [[0, 60, 120, 180, 240], [3.0, 2.6, 2.0, 2.4, 2.8], 2.5]', [[0, 60, 120, 180, 240], [3.0, 2.6, 2.0, 2.4, 2.8], 2.5], [[0, 70], [195, 240]]), ('tidal height window [[0, 60, 120, 180, 240], [2.5, 2.6, 2.0, 2.4, 2.8], 2.5]', [[0, 60, 120, 180, 240], [2.5, 2.6, 2.0, 2.4, 2.8], 2.5], [[0, 70], [195, 240]]), ('tidal height window [[0, 30, 60, 90, 120], [1.0, 2.0, 3.0, 2.0, 1.0], 2.0]', [[0, 30, 60, 90, 120], [1.0, 2.0, 3.0, 2.0, 1.0], 2.0], [[30, 90]]), ('tidal height window [[0, 45, 90, 135], [0.5, 0.7, 0.9, 0.6], 2.0]', [[0, 45, 90, 135], [0.5, 0.7, 0.9, 0.6], 2.0], [])]]
for label, args, expected in fixtures[N-1]:
    check(label, solve(args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
tidal height window [[0, 60, 120, 180, 240, 300, 360], [1.0, 1.8, 2.9, 3.6, 3.1, 2.2, 1.4], 2.5][[98, 280]][[99, 280]]Failed
tidal height window [[0, 60, 120, 180, 240, 300, 360], [1.0, 1.8, 2.9, 3.6, 3.1, 2.2, 1.4], 3.3][[154, 216]][[155, 216]]Failed
tidal height window [[0, 60, 120, 180, 240], [3.0, 2.6, 2.0, 2.4, 2.8], 2.5][[0, 70], [195, 240]][[0, 70], [195, 240]]Passed
tidal height window [[0, 60, 120, 180, 240], [2.5, 2.6, 2.0, 2.4, 2.8], 2.5][[0, 70], [195, 240]][[0, 70], [195, 240]]Passed
tidal height window [[0, 30, 60, 90, 120], [1.0, 2.0, 3.0, 2.0, 1.0], 2.0][[30, 90]][[30, 90]]Passed
tidal height window [[0, 45, 90, 135], [0.5, 0.7, 0.9, 0.6], 2.0][][]Passed
tidal height window [[0, 60, 120], [2.1, 2.2, 2.3], 2.0][[0, 120]][[0, 120]]Passed

SHA-256 / f650b0bafcd248812e41df01dcdc761e844056c40ece2abe4fb7cbf7e3a8593a

HELD IN THE MEMBER ARCHIVE

The verified repair and its recorded checks are member-only.

This mechanism has 7 recorded checks per implementation. The open-access tier publishes the failure and the unsuccessful fix; the repaired source that passes every check, and the observations that prove it, are available to members.

Every case sharing this mechanism uses the same contract and the same repair, so this one record is held back for all of them.

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Verification & scope

A deterministic toy model with stipulated rules and constants; not certified hydrographic software or a substitute for official tide tables. This reproducer isolates one failure mechanism. Results cover the supplied fixtures. Variants within a family share a test contract and should remain grouped when constructing evaluation splits. Related mechanisms with a shared evaluation_group must also remain together; these controlled models are not independent production incidents.

Observations recorded using Python 3.12.14 at 2026-09-29T14:48:08.164823+00:00.

Case digest / 0f7972f215886551d34dc76886d2300fb41e2c8b337eac343157813a629d2caf