FAILURE MAP
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FA-71581 / Seismic magnitude estimation / Open access

Clipping-aware amplitude pick: adjacent swing versus range · case 01

Non-adjacent extremes several cycles apart are combined into one swing.

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

ROOT CAUSE

The global range is used instead of consecutive turning points.

VERIFIED REPAIR

Use the largest difference between consecutive turning points.

Unsuccessful approach: Doubling the largest excursion from zero ignores the baseline of the swing.

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(turn) - min(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 6', [[30, -40, 30, -500], 1000], ['ok', 265.0]], ['segment 20', [[-40, 30, 0, 30, 450, 450], 1000], ['ok', 225.0]]], [['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 20', [[-40, 30, 0, 30, 450, 450], 1000], ['ok', 225.0]], ['end swing', [[0, 10, 5, 400], 1000], ['ok', 197.5]]], [['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 20', [[-40, 30, 0, 30, 450, 450], 1000], ['ok', 225.0]], ['plateau peak', [[0, 300, 300, -100, 0], 1000], ['ok', 200.0]]], [['segment 6', [[30, -40, 30, -500], 1000], ['ok', 265.0]], ['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]], ['end swing', [[0, 10, 5, 400], 1000], ['ok', 197.5]]], [['segment 20', [[-40, 30, 0, 30, 450, 450], 1000], ['ok', 225.0]], ['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]]]]
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 6['ok', 265.0]['ok', 265.0]Passed
segment 20['ok', 245.0]['ok', 225.0]Failed

SHA-256 / 52098e87332fcf04a29fa4585e52850a333e93b75d9e331a48657dda1a089262

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) >= 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(t) for t in turn) * 2
    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 6', [[30, -40, 30, -500], 1000], ['ok', 265.0]], ['segment 20', [[-40, 30, 0, 30, 450, 450], 1000], ['ok', 225.0]]], [['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 20', [[-40, 30, 0, 30, 450, 450], 1000], ['ok', 225.0]], ['end swing', [[0, 10, 5, 400], 1000], ['ok', 197.5]]], [['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 20', [[-40, 30, 0, 30, 450, 450], 1000], ['ok', 225.0]], ['plateau peak', [[0, 300, 300, -100, 0], 1000], ['ok', 200.0]]], [['segment 6', [[30, -40, 30, -500], 1000], ['ok', 265.0]], ['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]], ['end swing', [[0, 10, 5, 400], 1000], ['ok', 197.5]]], [['segment 20', [[-40, 30, 0, 30, 450, 450], 1000], ['ok', 225.0]], ['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]]]]
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', 900.0]['ok', 675.0]Failed
segment 3['clipped', None]['clipped', None]Passed
segment 4['clipped', None]['clipped', None]Passed
segment 5['clipped', None]['clipped', None]Passed
segment 6['ok', 500.0]['ok', 265.0]Failed
segment 20['ok', 450.0]['ok', 225.0]Failed

SHA-256 / 13f3c595a9005c2c6d050a4b34a6630efc4ed3f153af26aa26dab0b06ecd1ede

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 6', [[30, -40, 30, -500], 1000], ['ok', 265.0]], ['segment 20', [[-40, 30, 0, 30, 450, 450], 1000], ['ok', 225.0]]], [['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 20', [[-40, 30, 0, 30, 450, 450], 1000], ['ok', 225.0]], ['end swing', [[0, 10, 5, 400], 1000], ['ok', 197.5]]], [['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 20', [[-40, 30, 0, 30, 450, 450], 1000], ['ok', 225.0]], ['plateau peak', [[0, 300, 300, -100, 0], 1000], ['ok', 200.0]]], [['segment 6', [[30, -40, 30, -500], 1000], ['ok', 265.0]], ['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]], ['end swing', [[0, 10, 5, 400], 1000], ['ok', 197.5]]], [['segment 20', [[-40, 30, 0, 30, 450, 450], 1000], ['ok', 225.0]], ['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]]]]
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 6['ok', 265.0]['ok', 265.0]Passed
segment 20['ok', 225.0]['ok', 225.0]Passed

SHA-256 / 5aa8316de36a29c07633f0e9abe2003db56d28b84870b64f9aa067de246669bd

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 2026-09-29T14:48:30.964453+00:00.

Case digest / e282220d786386ca871e8d979ca40ff05a18993e45f28bbbd64d486e43706de9