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FA-71721 / Seismic magnitude estimation / Open access

Regional conversion to Mw: Ms branch boundary · case 01

Ms 6.1 converts with the large-magnitude relation.

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

ROOT CAUSE

The small-Ms relation excludes 6.1.

VERIFIED REPAIR

Use 0.67 Ms + 2.07 through 6.1 inclusive.

Unsuccessful approach: Ending the small-Ms relation below 6.0 converts 6.0 with the large-magnitude relation.

Case contract

Case-sensitive type. ML: < 3.5 -> 0.8 ML + 0.6; 3.5..6.0 -> ML; > 6.0 None. mb: 3.5..6.2 -> 1.54 mb - 2.54, else None. Ms: <= 6.1 -> 0.67 Ms + 2.07; 6.1 < Ms <= 8.2 -> 0.99 Ms + 0.08; else None. Other types None. Round half up to 0.1 via floor(x*10 + 0.5)/10.

Why this case matters

Homogenised catalogues convert heterogeneous magnitudes to a common Mw.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
import math
N = 1
observations = []
def solve(mtype, value):
    if mtype == "ML":
        if value > 6.0:
            return None
        x = 0.8 * value + 0.6 if value < 3.5 else value
    elif mtype == "mb":
        if not (3.5 <= value <= 6.2):
            return None
        x = 1.54 * value - 2.54
    elif mtype == "Ms":
        if value > 8.2:
            return None
        x = 0.67 * value + 2.07 if value < 6.1 else 0.99 * value + 0.08
    else:
        return None
    return math.floor(x * 10 + 0.5) / 10
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['ML 2.0', ['ML', 2.0], 2.2], ['ML 3.4', ['ML', 3.4], 3.3], ['ML 3.5', ['ML', 3.5], 3.5], ['ML 4.8', ['ML', 4.8], 4.8], ['ML 6.0', ['ML', 6.0], 6.0], ['ML 6.1', ['ML', 6.1], None], ['ML 6.9', ['ML', 6.9], None], ['Ms 6.1', ['Ms', 6.1], 6.2]], [['mb 3.4', ['mb', 3.4], None], ['mb 3.5', ['mb', 3.5], 2.9], ['mb 5.0', ['mb', 5.0], 5.2], ['mb 6.2', ['mb', 6.2], 7.0], ['mb 6.3', ['mb', 6.3], None], ['Ms 4.0', ['Ms', 4.0], 4.8], ['Ms 6.0', ['Ms', 6.0], 6.1], ['Ms 6.1', ['Ms', 6.1], 6.2]], [['ML 2.0', ['ML', 2.0], 2.2], ['ML 3.4', ['ML', 3.4], 3.3], ['Ms 6.1', ['Ms', 6.1], 6.2], ['Ms 6.2', ['Ms', 6.2], 6.2], ['Ms 8.2', ['Ms', 8.2], 8.2], ['Ms 8.3', ['Ms', 8.3], None], ['Md 3.0', ['Md', 3.0], None], ['ml 4.0', ['ml', 4.0], None]], [['ML 3.4', ['ML', 3.4], 3.3], ['ML 3.5', ['ML', 3.5], 3.5], ['ML 4.8', ['ML', 4.8], 4.8], ['ML 6.0', ['ML', 6.0], 6.0], ['ML 6.1', ['ML', 6.1], None], ['ML 6.9', ['ML', 6.9], None], ['Ms 6.0', ['Ms', 6.0], 6.1], ['Ms 6.1', ['Ms', 6.1], 6.2]], [['mb 3.5', ['mb', 3.5], 2.9], ['mb 5.0', ['mb', 5.0], 5.2], ['mb 6.2', ['mb', 6.2], 7.0], ['mb 6.3', ['mb', 6.3], None], ['Ms 4.0', ['Ms', 4.0], 4.8], ['Ms 6.0', ['Ms', 6.0], 6.1], ['Ms 6.1', ['Ms', 6.1], 6.2], ['Ms 6.2', ['Ms', 6.2], 6.2]]]
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
ML 2.02.22.2Passed
ML 3.43.33.3Passed
ML 3.53.53.5Passed
ML 4.84.84.8Passed
ML 6.06.06.0Passed
ML 6.1NoneNonePassed
ML 6.9NoneNonePassed
Ms 6.16.16.2Failed

SHA-256 / 05be0cc4a2392ced4dc90fdf14d8ca2660723ac5ab62495d4a384064b0fea9b2

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
import math
N = 1
observations = []
def solve(mtype, value):
    if mtype == "ML":
        if value > 6.0:
            return None
        x = 0.8 * value + 0.6 if value < 3.5 else value
    elif mtype == "mb":
        if not (3.5 <= value <= 6.2):
            return None
        x = 1.54 * value - 2.54
    elif mtype == "Ms":
        if value > 8.2:
            return None
        x = 0.67 * value + 2.07 if value < 6.0 else 0.99 * value + 0.08
    else:
        return None
    return math.floor(x * 10 + 0.5) / 10
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['ML 2.0', ['ML', 2.0], 2.2], ['ML 3.4', ['ML', 3.4], 3.3], ['ML 3.5', ['ML', 3.5], 3.5], ['ML 4.8', ['ML', 4.8], 4.8], ['ML 6.0', ['ML', 6.0], 6.0], ['ML 6.1', ['ML', 6.1], None], ['ML 6.9', ['ML', 6.9], None], ['Ms 6.1', ['Ms', 6.1], 6.2]], [['mb 3.4', ['mb', 3.4], None], ['mb 3.5', ['mb', 3.5], 2.9], ['mb 5.0', ['mb', 5.0], 5.2], ['mb 6.2', ['mb', 6.2], 7.0], ['mb 6.3', ['mb', 6.3], None], ['Ms 4.0', ['Ms', 4.0], 4.8], ['Ms 6.0', ['Ms', 6.0], 6.1], ['Ms 6.1', ['Ms', 6.1], 6.2]], [['ML 2.0', ['ML', 2.0], 2.2], ['ML 3.4', ['ML', 3.4], 3.3], ['Ms 6.1', ['Ms', 6.1], 6.2], ['Ms 6.2', ['Ms', 6.2], 6.2], ['Ms 8.2', ['Ms', 8.2], 8.2], ['Ms 8.3', ['Ms', 8.3], None], ['Md 3.0', ['Md', 3.0], None], ['ml 4.0', ['ml', 4.0], None]], [['ML 3.4', ['ML', 3.4], 3.3], ['ML 3.5', ['ML', 3.5], 3.5], ['ML 4.8', ['ML', 4.8], 4.8], ['ML 6.0', ['ML', 6.0], 6.0], ['ML 6.1', ['ML', 6.1], None], ['ML 6.9', ['ML', 6.9], None], ['Ms 6.0', ['Ms', 6.0], 6.1], ['Ms 6.1', ['Ms', 6.1], 6.2]], [['mb 3.5', ['mb', 3.5], 2.9], ['mb 5.0', ['mb', 5.0], 5.2], ['mb 6.2', ['mb', 6.2], 7.0], ['mb 6.3', ['mb', 6.3], None], ['Ms 4.0', ['Ms', 4.0], 4.8], ['Ms 6.0', ['Ms', 6.0], 6.1], ['Ms 6.1', ['Ms', 6.1], 6.2], ['Ms 6.2', ['Ms', 6.2], 6.2]]]
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
ML 2.02.22.2Passed
ML 3.43.33.3Passed
ML 3.53.53.5Passed
ML 4.84.84.8Passed
ML 6.06.06.0Passed
ML 6.1NoneNonePassed
ML 6.9NoneNonePassed
Ms 6.16.16.2Failed

SHA-256 / 64b599ea07c4ed63c57cbcbe3827c69bfe38725c87694552e659a4c68849bee4

3 / The verified repair

Exit 0
"""Failure Map reference implementation. Python standard library only."""
import json
import math
N = 1
observations = []
def solve(mtype, value):
    if mtype == "ML":
        if value > 6.0:
            return None
        x = 0.8 * value + 0.6 if value < 3.5 else value
    elif mtype == "mb":
        if not (3.5 <= value <= 6.2):
            return None
        x = 1.54 * value - 2.54
    elif mtype == "Ms":
        if value > 8.2:
            return None
        x = 0.67 * value + 2.07 if value <= 6.1 else 0.99 * value + 0.08
    else:
        return None
    return math.floor(x * 10 + 0.5) / 10
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['ML 2.0', ['ML', 2.0], 2.2], ['ML 3.4', ['ML', 3.4], 3.3], ['ML 3.5', ['ML', 3.5], 3.5], ['ML 4.8', ['ML', 4.8], 4.8], ['ML 6.0', ['ML', 6.0], 6.0], ['ML 6.1', ['ML', 6.1], None], ['ML 6.9', ['ML', 6.9], None], ['Ms 6.1', ['Ms', 6.1], 6.2]], [['mb 3.4', ['mb', 3.4], None], ['mb 3.5', ['mb', 3.5], 2.9], ['mb 5.0', ['mb', 5.0], 5.2], ['mb 6.2', ['mb', 6.2], 7.0], ['mb 6.3', ['mb', 6.3], None], ['Ms 4.0', ['Ms', 4.0], 4.8], ['Ms 6.0', ['Ms', 6.0], 6.1], ['Ms 6.1', ['Ms', 6.1], 6.2]], [['ML 2.0', ['ML', 2.0], 2.2], ['ML 3.4', ['ML', 3.4], 3.3], ['Ms 6.1', ['Ms', 6.1], 6.2], ['Ms 6.2', ['Ms', 6.2], 6.2], ['Ms 8.2', ['Ms', 8.2], 8.2], ['Ms 8.3', ['Ms', 8.3], None], ['Md 3.0', ['Md', 3.0], None], ['ml 4.0', ['ml', 4.0], None]], [['ML 3.4', ['ML', 3.4], 3.3], ['ML 3.5', ['ML', 3.5], 3.5], ['ML 4.8', ['ML', 4.8], 4.8], ['ML 6.0', ['ML', 6.0], 6.0], ['ML 6.1', ['ML', 6.1], None], ['ML 6.9', ['ML', 6.9], None], ['Ms 6.0', ['Ms', 6.0], 6.1], ['Ms 6.1', ['Ms', 6.1], 6.2]], [['mb 3.5', ['mb', 3.5], 2.9], ['mb 5.0', ['mb', 5.0], 5.2], ['mb 6.2', ['mb', 6.2], 7.0], ['mb 6.3', ['mb', 6.3], None], ['Ms 4.0', ['Ms', 4.0], 4.8], ['Ms 6.0', ['Ms', 6.0], 6.1], ['Ms 6.1', ['Ms', 6.1], 6.2], ['Ms 6.2', ['Ms', 6.2], 6.2]]]
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
ML 2.02.22.2Passed
ML 3.43.33.3Passed
ML 3.53.53.5Passed
ML 4.84.84.8Passed
ML 6.06.06.0Passed
ML 6.1NoneNonePassed
ML 6.9NoneNonePassed
Ms 6.16.26.2Passed

SHA-256 / f1e424cbcbc515182a35797301dc7570f4c22e9027aa3067107fd8f9305166cf

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 2026-09-29T14:48:32.229561+00:00.

Case digest / 3e95da7e66166ca4bb5bf43cae3528735eccd0ac8f7cbebd584132137989cc6f