FAILURE MAP
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FA-71571 / Seismic magnitude estimation / Open access

Clipping-aware amplitude pick: clip threshold inclusivity · case 01

A record touching 95% of full scale is used for magnitude.

Verified by executionVariant 1 · 8 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The clip test is exclusive at the threshold.

VERIFIED REPAIR

Treat |s| >= 0.95*full scale as clipped.

Unsuccessful approach: Testing against 100% full scale misses near-saturation clipping.

Case contract

Integer counts. If any |sample| >= 0.95*full_scale (integer-truncated) return ["clipped", None]. Otherwise turning points are the first sample, every interior sample that is a peak (b > a and b >= c) or trough (b < a and b <= c), and the last sample; the amplitude is half the largest absolute difference between consecutive turning points. Return ["ok", amplitude].

Why this case matters

Magnitude amplitudes must not come from clipped records and use half peak-to-trough swings.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(samples, full_scale):
    limit = int(full_scale * 0.95)
    if any(abs(s) > limit for s in samples):
        return ["clipped", None]
    turn = [samples[0]]
    for i in range(1, len(samples) - 1):
        a, b, c = samples[i - 1], samples[i], samples[i + 1]
        if (b > a and b >= c) or (b < a and b <= c):
            turn.append(b)
    turn.append(samples[-1])
    best = max(abs(turn[i] - turn[i - 1]) for i in range(1, len(turn)))
    return ["ok", best / 2]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['segment 0', [[30, -120, 1000], 1000], ['clipped', None]], ['segment 1', [[-500, 30, 1000, 1000, 1000, 200, 450], 1000], ['clipped', None]], ['segment 2', [[-900, 200, 450], 1000], ['ok', 675.0]], ['segment 3', [[-120, 0, -120, -900, 200, -900, 1000, 200], 1000], ['clipped', None]], ['segment 4', [[30, -120, 1000, 1000, -120, 1000], 1000], ['clipped', None]], ['segment 5', [[1000, 1000, -900], 1000], ['clipped', None]], ['segment 7', [[-120, 950, 200, 450], 1000], ['clipped', None]], ['segment 15', [[-900, 30, -900, 30, 0, 950, 950], 1000], ['clipped', None]]], [['segment 7', [[-120, 950, 200, 450], 1000], ['clipped', None]], ['segment 8', [[1000, 200, 450, -120], 1000], ['clipped', None]], ['segment 9', [[-120, 1000, -40, -120, 450], 1000], ['clipped', None]], ['segment 10', [[200, 1000, -40], 1000], ['clipped', None]], ['segment 11', [[1000, 450, -900, 0, 1000], 1000], ['clipped', None]], ['segment 12', [[950, 0, 1000], 1000], ['clipped', None]], ['segment 28', [[-40, 200, 950, -500], 1000], ['clipped', None]], ['segment 32', [[-900, 950, 450, 30, 450], 1000], ['clipped', None]]], [['segment 14', [[-40, 30, 450], 1000], ['ok', 245.0]], ['segment 15', [[-900, 30, -900, 30, 0, 950, 950], 1000], ['clipped', None]], ['segment 16', [[-900, -500, -500], 1000], ['ok', 200.0]], ['segment 17', [[-500, -120, 1000, -120], 1000], ['clipped', None]], ['segment 18', [[950, -40, 450], 1000], ['clipped', None]], ['segment 19', [[-500, 30, -500, 200, -120], 1000], ['ok', 350.0]], ['segment 28', [[-40, 200, 950, -500], 1000], ['clipped', None]], ['segment 32', [[-900, 950, 450, 30, 450], 1000], ['clipped', None]]], [['segment 7', [[-120, 950, 200, 450], 1000], ['clipped', None]], ['segment 15', [[-900, 30, -900, 30, 0, 950, 950], 1000], ['clipped', None]], ['segment 21', [[1000, -900, 200, -120, 1000, 1000, 200], 1000], ['clipped', None]], ['segment 22', [[-500, -900, -40], 1000], ['ok', 430.0]], ['segment 23', [[30, 0, 450, 450, 450, -900], 1000], ['ok', 675.0]], ['segment 24', [[30, -500, 450, 30, -40], 1000], ['ok', 475.0]], ['segment 25', [[-120, -500, -500, 30], 1000], ['ok', 265.0]], ['segment 26', [[1000, 1000, 0, 30, 0, 30, -120, -900, -900], 1000], ['clipped', None]]], [['segment 28', [[-40, 200, 950, -500], 1000], ['clipped', None]], ['segment 29', [[450, 950, 950, -900, 450, 30, 950, 950, 30], 1000], ['clipped', None]], ['segment 30', [[-40, 30, -40, 1000, -900, 950, 30, 1000, -500], 1000], ['clipped', None]], ['segment 31', [[200, -900, -120, -500, -120, 950, -500, 30, 450], 1000], ['clipped', None]], ['segment 32', [[-900, 950, 450, 30, 450], 1000], ['clipped', None]], ['segment 33', [[0, 30, 1000, 30, -900], 1000], ['clipped', None]], ['exactly at clip threshold', [[0, 950, -100, 20], 1000], ['clipped', None]], ['plateau peak', [[0, 300, 300, -100, 0], 1000], ['ok', 200.0]]]]
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
segment 0['clipped', None]['clipped', None]Passed
segment 1['clipped', None]['clipped', None]Passed
segment 2['ok', 675.0]['ok', 675.0]Passed
segment 3['clipped', None]['clipped', None]Passed
segment 4['clipped', None]['clipped', None]Passed
segment 5['clipped', None]['clipped', None]Passed
segment 7['ok', 535.0]['clipped', None]Failed
segment 15['ok', 475.0]['clipped', None]Failed

SHA-256 / 1875d44708cc9844d53bb4aeae02263b891582c08f8477fc1abadf29850a45a5

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(samples, full_scale):
    limit = int(full_scale * 0.95)
    if any(abs(s) >= full_scale for s in samples):
        return ["clipped", None]
    turn = [samples[0]]
    for i in range(1, len(samples) - 1):
        a, b, c = samples[i - 1], samples[i], samples[i + 1]
        if (b > a and b >= c) or (b < a and b <= c):
            turn.append(b)
    turn.append(samples[-1])
    best = max(abs(turn[i] - turn[i - 1]) for i in range(1, len(turn)))
    return ["ok", best / 2]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['segment 0', [[30, -120, 1000], 1000], ['clipped', None]], ['segment 1', [[-500, 30, 1000, 1000, 1000, 200, 450], 1000], ['clipped', None]], ['segment 2', [[-900, 200, 450], 1000], ['ok', 675.0]], ['segment 3', [[-120, 0, -120, -900, 200, -900, 1000, 200], 1000], ['clipped', None]], ['segment 4', [[30, -120, 1000, 1000, -120, 1000], 1000], ['clipped', None]], ['segment 5', [[1000, 1000, -900], 1000], ['clipped', None]], ['segment 7', [[-120, 950, 200, 450], 1000], ['clipped', None]], ['segment 15', [[-900, 30, -900, 30, 0, 950, 950], 1000], ['clipped', None]]], [['segment 7', [[-120, 950, 200, 450], 1000], ['clipped', None]], ['segment 8', [[1000, 200, 450, -120], 1000], ['clipped', None]], ['segment 9', [[-120, 1000, -40, -120, 450], 1000], ['clipped', None]], ['segment 10', [[200, 1000, -40], 1000], ['clipped', None]], ['segment 11', [[1000, 450, -900, 0, 1000], 1000], ['clipped', None]], ['segment 12', [[950, 0, 1000], 1000], ['clipped', None]], ['segment 28', [[-40, 200, 950, -500], 1000], ['clipped', None]], ['segment 32', [[-900, 950, 450, 30, 450], 1000], ['clipped', None]]], [['segment 14', [[-40, 30, 450], 1000], ['ok', 245.0]], ['segment 15', [[-900, 30, -900, 30, 0, 950, 950], 1000], ['clipped', None]], ['segment 16', [[-900, -500, -500], 1000], ['ok', 200.0]], ['segment 17', [[-500, -120, 1000, -120], 1000], ['clipped', None]], ['segment 18', [[950, -40, 450], 1000], ['clipped', None]], ['segment 19', [[-500, 30, -500, 200, -120], 1000], ['ok', 350.0]], ['segment 28', [[-40, 200, 950, -500], 1000], ['clipped', None]], ['segment 32', [[-900, 950, 450, 30, 450], 1000], ['clipped', None]]], [['segment 7', [[-120, 950, 200, 450], 1000], ['clipped', None]], ['segment 15', [[-900, 30, -900, 30, 0, 950, 950], 1000], ['clipped', None]], ['segment 21', [[1000, -900, 200, -120, 1000, 1000, 200], 1000], ['clipped', None]], ['segment 22', [[-500, -900, -40], 1000], ['ok', 430.0]], ['segment 23', [[30, 0, 450, 450, 450, -900], 1000], ['ok', 675.0]], ['segment 24', [[30, -500, 450, 30, -40], 1000], ['ok', 475.0]], ['segment 25', [[-120, -500, -500, 30], 1000], ['ok', 265.0]], ['segment 26', [[1000, 1000, 0, 30, 0, 30, -120, -900, -900], 1000], ['clipped', None]]], [['segment 28', [[-40, 200, 950, -500], 1000], ['clipped', None]], ['segment 29', [[450, 950, 950, -900, 450, 30, 950, 950, 30], 1000], ['clipped', None]], ['segment 30', [[-40, 30, -40, 1000, -900, 950, 30, 1000, -500], 1000], ['clipped', None]], ['segment 31', [[200, -900, -120, -500, -120, 950, -500, 30, 450], 1000], ['clipped', None]], ['segment 32', [[-900, 950, 450, 30, 450], 1000], ['clipped', None]], ['segment 33', [[0, 30, 1000, 30, -900], 1000], ['clipped', None]], ['exactly at clip threshold', [[0, 950, -100, 20], 1000], ['clipped', None]], ['plateau peak', [[0, 300, 300, -100, 0], 1000], ['ok', 200.0]]]]
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
segment 0['clipped', None]['clipped', None]Passed
segment 1['clipped', None]['clipped', None]Passed
segment 2['ok', 675.0]['ok', 675.0]Passed
segment 3['clipped', None]['clipped', None]Passed
segment 4['clipped', None]['clipped', None]Passed
segment 5['clipped', None]['clipped', None]Passed
segment 7['ok', 535.0]['clipped', None]Failed
segment 15['ok', 475.0]['clipped', None]Failed

SHA-256 / 1a2c8539debe37927c54e867c4407188fe1cd17fa0193662a6adc6d0ca2f33e1

3 / The verified repair

Exit 0
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(samples, full_scale):
    limit = int(full_scale * 0.95)
    if any(abs(s) >= limit for s in samples):
        return ["clipped", None]
    turn = [samples[0]]
    for i in range(1, len(samples) - 1):
        a, b, c = samples[i - 1], samples[i], samples[i + 1]
        if (b > a and b >= c) or (b < a and b <= c):
            turn.append(b)
    turn.append(samples[-1])
    best = max(abs(turn[i] - turn[i - 1]) for i in range(1, len(turn)))
    return ["ok", best / 2]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['segment 0', [[30, -120, 1000], 1000], ['clipped', None]], ['segment 1', [[-500, 30, 1000, 1000, 1000, 200, 450], 1000], ['clipped', None]], ['segment 2', [[-900, 200, 450], 1000], ['ok', 675.0]], ['segment 3', [[-120, 0, -120, -900, 200, -900, 1000, 200], 1000], ['clipped', None]], ['segment 4', [[30, -120, 1000, 1000, -120, 1000], 1000], ['clipped', None]], ['segment 5', [[1000, 1000, -900], 1000], ['clipped', None]], ['segment 7', [[-120, 950, 200, 450], 1000], ['clipped', None]], ['segment 15', [[-900, 30, -900, 30, 0, 950, 950], 1000], ['clipped', None]]], [['segment 7', [[-120, 950, 200, 450], 1000], ['clipped', None]], ['segment 8', [[1000, 200, 450, -120], 1000], ['clipped', None]], ['segment 9', [[-120, 1000, -40, -120, 450], 1000], ['clipped', None]], ['segment 10', [[200, 1000, -40], 1000], ['clipped', None]], ['segment 11', [[1000, 450, -900, 0, 1000], 1000], ['clipped', None]], ['segment 12', [[950, 0, 1000], 1000], ['clipped', None]], ['segment 28', [[-40, 200, 950, -500], 1000], ['clipped', None]], ['segment 32', [[-900, 950, 450, 30, 450], 1000], ['clipped', None]]], [['segment 14', [[-40, 30, 450], 1000], ['ok', 245.0]], ['segment 15', [[-900, 30, -900, 30, 0, 950, 950], 1000], ['clipped', None]], ['segment 16', [[-900, -500, -500], 1000], ['ok', 200.0]], ['segment 17', [[-500, -120, 1000, -120], 1000], ['clipped', None]], ['segment 18', [[950, -40, 450], 1000], ['clipped', None]], ['segment 19', [[-500, 30, -500, 200, -120], 1000], ['ok', 350.0]], ['segment 28', [[-40, 200, 950, -500], 1000], ['clipped', None]], ['segment 32', [[-900, 950, 450, 30, 450], 1000], ['clipped', None]]], [['segment 7', [[-120, 950, 200, 450], 1000], ['clipped', None]], ['segment 15', [[-900, 30, -900, 30, 0, 950, 950], 1000], ['clipped', None]], ['segment 21', [[1000, -900, 200, -120, 1000, 1000, 200], 1000], ['clipped', None]], ['segment 22', [[-500, -900, -40], 1000], ['ok', 430.0]], ['segment 23', [[30, 0, 450, 450, 450, -900], 1000], ['ok', 675.0]], ['segment 24', [[30, -500, 450, 30, -40], 1000], ['ok', 475.0]], ['segment 25', [[-120, -500, -500, 30], 1000], ['ok', 265.0]], ['segment 26', [[1000, 1000, 0, 30, 0, 30, -120, -900, -900], 1000], ['clipped', None]]], [['segment 28', [[-40, 200, 950, -500], 1000], ['clipped', None]], ['segment 29', [[450, 950, 950, -900, 450, 30, 950, 950, 30], 1000], ['clipped', None]], ['segment 30', [[-40, 30, -40, 1000, -900, 950, 30, 1000, -500], 1000], ['clipped', None]], ['segment 31', [[200, -900, -120, -500, -120, 950, -500, 30, 450], 1000], ['clipped', None]], ['segment 32', [[-900, 950, 450, 30, 450], 1000], ['clipped', None]], ['segment 33', [[0, 30, 1000, 30, -900], 1000], ['clipped', None]], ['exactly at clip threshold', [[0, 950, -100, 20], 1000], ['clipped', None]], ['plateau peak', [[0, 300, 300, -100, 0], 1000], ['ok', 200.0]]]]
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
segment 0['clipped', None]['clipped', None]Passed
segment 1['clipped', None]['clipped', None]Passed
segment 2['ok', 675.0]['ok', 675.0]Passed
segment 3['clipped', None]['clipped', None]Passed
segment 4['clipped', None]['clipped', None]Passed
segment 5['clipped', None]['clipped', None]Passed
segment 7['clipped', None]['clipped', None]Passed
segment 15['clipped', None]['clipped', None]Passed

SHA-256 / faaf74e53ab835204681516ff11bf3a32d25a04dea2f0c5cb063a94078b52192

Verification & scope

Stipulated deterministic teaching model of a seismological magnitude procedure; constants and tables are fixed by the contract and no claim of agency or standards conformance is made. 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 2026-09-29T14:48:30.883068+00:00.

Case digest / 6ff97fe6123c6205cdd75a912046b597b4672385804901de5ec4e2ac097fe5c1