FAILURE MAP
← Case archive

FA-95431 / Shipping rate zone lookup / Open access

Surcharges: fuel cents truncated · case 01

Fuel surcharges are a cent low on roughly half of shipments.

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

ROOT CAUSE

The fuel amount is floor-divided instead of rounded half up.

THE FAILURE

The fuel amount is floor-divided instead of rounded half up.

Unsuccessful approach: Python round() rounds exact half cents to even.

Case contract

Cents. Residential 550; delivery area DAS 395 or EXT 510, plus 100 when the delivery is residential. Fuel = fuel_bp basis points of (base + residential + delivery area), rounded half up to the cent. Declared value (whole dollars): first $100 free, then 105 cents per $100 or part. Return [fuel, declared_value_fee, total].

Why this case matters

Accessorials and fuel are layered on the zone rate in a fixed order.

1 / The failure

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

N = 1
observations = []
def solve(base, residential, das, declared, fuel_bp):
    res = 550 if residential else 0
    das_fee = {'NONE': 0, 'DAS': 395, 'EXT': 510}[das]
    if residential and das != 'NONE':
        das_fee += 100
    subject = base + res + das_fee
    fuel = subject * fuel_bp // 10000
    excess = max(0, declared - 100)
    dv = -(-excess // 100) * 105
    return [fuel, dv, subject + fuel + dv]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['fuel exact half', [1012, False, 'NONE', 0, 1250], [127, 0, 1139]], ['generated mix 30', [2345, False, 'DAS', 250, 1250], [343, 210, 3293]], ['commercial das', [1000, False, 'DAS', 0, 1500], [209, 0, 1604]], ['half cent up', [1000, False, 'NONE', 0, 1250], [125, 0, 1125]], ['declared exactly 100', [2000, False, 'NONE', 100, 1000], [200, 0, 2200]], ['residential ext uplift', [1000, True, 'EXT', 0, 1000], [216, 0, 2376]], ['generated mix 6', [1500, True, 'EXT', 100, 1500], [399, 0, 3059]], ['generated mix 14', [2345, True, 'EXT', 1000, 1250], [438, 945, 4888]]], [['generated mix 20', [1000, True, 'DAS', 250, 1500], [307, 210, 2562]], ['generated mix 67', [2345, False, 'DAS', 50, 1250], [343, 0, 3083]], ['fuel exact half', [1012, False, 'NONE', 0, 1250], [127, 0, 1139]], ['declared exactly 100', [2000, False, 'NONE', 100, 1000], [200, 0, 2200]], ['commercial das', [1000, False, 'DAS', 0, 1500], [209, 0, 1604]], ['half cent up', [1000, False, 'NONE', 0, 1250], [125, 0, 1125]], ['generated mix 9', [4000, True, 'EXT', 100, 1250], [645, 0, 5805]], ['generated mix 17', [2345, False, 'DAS', 250, 1625], [445, 210, 3395]]], [['generated mix 42', [4000, False, 'EXT', 200, 1250], [564, 105, 5179]], ['generated mix 49', [4000, False, 'EXT', 200, 1500], [677, 105, 5292]], ['declared 250', [2000, True, 'NONE', 250, 1000], [255, 210, 3015]], ['residential ext uplift', [1000, True, 'EXT', 0, 1000], [216, 0, 2376]], ['fuel exact half', [1012, False, 'NONE', 0, 1250], [127, 0, 1139]], ['declared exactly 100', [2000, False, 'NONE', 100, 1000], [200, 0, 2200]], ['generated mix 20', [1000, True, 'DAS', 250, 1500], [307, 210, 2562]], ['generated mix 28', [1234, False, 'EXT', 100, 1625], [283, 0, 2027]]], [['generated mix 66', [2345, False, 'EXT', 50, 1250], [357, 0, 3212]], ['fuel exact half', [1012, False, 'NONE', 0, 1250], [127, 0, 1139]], ['declared part hundred', [2000, False, 'NONE', 101, 1000], [200, 105, 2305]], ['declared 250', [2000, True, 'NONE', 250, 1000], [255, 210, 3015]], ['residential ext uplift', [1000, True, 'EXT', 0, 1000], [216, 0, 2376]], ['generated mix 31', [2345, True, 'DAS', 50, 1850], [627, 0, 4017]], ['generated mix 39', [1234, False, 'DAS', 101, 1500], [244, 105, 1978]], ['generated mix 47', [1000, False, 'NONE', 1000, 1850], [185, 945, 2130]]], [['generated mix 3', [2345, True, 'EXT', 50, 1500], [526, 0, 4031]], ['generated mix 64', [1000, False, 'EXT', 100, 1500], [227, 0, 1737]], ['declared exactly 100', [2000, False, 'NONE', 100, 1000], [200, 0, 2200]], ['commercial das', [1000, False, 'DAS', 0, 1500], [209, 0, 1604]], ['half cent up', [1000, False, 'NONE', 0, 1250], [125, 0, 1125]], ['declared part hundred', [2000, False, 'NONE', 101, 1000], [200, 105, 2305]], ['generated mix 43', [1000, True, 'EXT', 1000, 1625], [351, 945, 3456]], ['generated mix 51', [2345, False, 'NONE', 250, 1625], [381, 210, 2936]]]]
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
fuel exact half[126, 0, 1138][127, 0, 1139]Failed
generated mix 30[342, 210, 3292][343, 210, 3293]Failed
commercial das[209, 0, 1604][209, 0, 1604]Passed
half cent up[125, 0, 1125][125, 0, 1125]Passed
declared exactly 100[200, 0, 2200][200, 0, 2200]Passed
residential ext uplift[216, 0, 2376][216, 0, 2376]Passed
generated mix 6[399, 0, 3059][399, 0, 3059]Passed
generated mix 14[438, 945, 4888][438, 945, 4888]Passed

SHA-256 / e9e24ba12e28a6d37c6b191b1468133b075dea4d5fa521b4c2a0400ef26dc856

2 / The unsuccessful fix

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

N = 1
observations = []
def solve(base, residential, das, declared, fuel_bp):
    res = 550 if residential else 0
    das_fee = {'NONE': 0, 'DAS': 395, 'EXT': 510}[das]
    if residential and das != 'NONE':
        das_fee += 100
    subject = base + res + das_fee
    fuel = round(subject * fuel_bp / 10000)
    excess = max(0, declared - 100)
    dv = -(-excess // 100) * 105
    return [fuel, dv, subject + fuel + dv]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['fuel exact half', [1012, False, 'NONE', 0, 1250], [127, 0, 1139]], ['generated mix 30', [2345, False, 'DAS', 250, 1250], [343, 210, 3293]], ['commercial das', [1000, False, 'DAS', 0, 1500], [209, 0, 1604]], ['half cent up', [1000, False, 'NONE', 0, 1250], [125, 0, 1125]], ['declared exactly 100', [2000, False, 'NONE', 100, 1000], [200, 0, 2200]], ['residential ext uplift', [1000, True, 'EXT', 0, 1000], [216, 0, 2376]], ['generated mix 6', [1500, True, 'EXT', 100, 1500], [399, 0, 3059]], ['generated mix 14', [2345, True, 'EXT', 1000, 1250], [438, 945, 4888]]], [['generated mix 20', [1000, True, 'DAS', 250, 1500], [307, 210, 2562]], ['generated mix 67', [2345, False, 'DAS', 50, 1250], [343, 0, 3083]], ['fuel exact half', [1012, False, 'NONE', 0, 1250], [127, 0, 1139]], ['declared exactly 100', [2000, False, 'NONE', 100, 1000], [200, 0, 2200]], ['commercial das', [1000, False, 'DAS', 0, 1500], [209, 0, 1604]], ['half cent up', [1000, False, 'NONE', 0, 1250], [125, 0, 1125]], ['generated mix 9', [4000, True, 'EXT', 100, 1250], [645, 0, 5805]], ['generated mix 17', [2345, False, 'DAS', 250, 1625], [445, 210, 3395]]], [['generated mix 42', [4000, False, 'EXT', 200, 1250], [564, 105, 5179]], ['generated mix 49', [4000, False, 'EXT', 200, 1500], [677, 105, 5292]], ['declared 250', [2000, True, 'NONE', 250, 1000], [255, 210, 3015]], ['residential ext uplift', [1000, True, 'EXT', 0, 1000], [216, 0, 2376]], ['fuel exact half', [1012, False, 'NONE', 0, 1250], [127, 0, 1139]], ['declared exactly 100', [2000, False, 'NONE', 100, 1000], [200, 0, 2200]], ['generated mix 20', [1000, True, 'DAS', 250, 1500], [307, 210, 2562]], ['generated mix 28', [1234, False, 'EXT', 100, 1625], [283, 0, 2027]]], [['generated mix 66', [2345, False, 'EXT', 50, 1250], [357, 0, 3212]], ['fuel exact half', [1012, False, 'NONE', 0, 1250], [127, 0, 1139]], ['declared part hundred', [2000, False, 'NONE', 101, 1000], [200, 105, 2305]], ['declared 250', [2000, True, 'NONE', 250, 1000], [255, 210, 3015]], ['residential ext uplift', [1000, True, 'EXT', 0, 1000], [216, 0, 2376]], ['generated mix 31', [2345, True, 'DAS', 50, 1850], [627, 0, 4017]], ['generated mix 39', [1234, False, 'DAS', 101, 1500], [244, 105, 1978]], ['generated mix 47', [1000, False, 'NONE', 1000, 1850], [185, 945, 2130]]], [['generated mix 3', [2345, True, 'EXT', 50, 1500], [526, 0, 4031]], ['generated mix 64', [1000, False, 'EXT', 100, 1500], [227, 0, 1737]], ['declared exactly 100', [2000, False, 'NONE', 100, 1000], [200, 0, 2200]], ['commercial das', [1000, False, 'DAS', 0, 1500], [209, 0, 1604]], ['half cent up', [1000, False, 'NONE', 0, 1250], [125, 0, 1125]], ['declared part hundred', [2000, False, 'NONE', 101, 1000], [200, 105, 2305]], ['generated mix 43', [1000, True, 'EXT', 1000, 1625], [351, 945, 3456]], ['generated mix 51', [2345, False, 'NONE', 250, 1625], [381, 210, 2936]]]]
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
fuel exact half[126, 0, 1138][127, 0, 1139]Failed
generated mix 30[342, 210, 3292][343, 210, 3293]Failed
commercial das[209, 0, 1604][209, 0, 1604]Passed
half cent up[125, 0, 1125][125, 0, 1125]Passed
declared exactly 100[200, 0, 2200][200, 0, 2200]Passed
residential ext uplift[216, 0, 2376][216, 0, 2376]Passed
generated mix 6[399, 0, 3059][399, 0, 3059]Passed
generated mix 14[438, 945, 4888][438, 945, 4888]Passed

SHA-256 / 50f1be1e2758ac3664e8e711b1c53de276c6506ceed5711ef678d859e3425aa2

HELD IN THE MEMBER ARCHIVE

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

This mechanism has 8 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.

Member access is invitation-based. Sign in with your invited account to inspect the repair.

Sign in to the archive ↗

Verification & scope

Stipulated fee amounts and ordering. 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 2026-09-29T14:52:13.640547+00:00.

Case digest / ffa2c651ccf935ed7c97a608450a8e0788c090b51943ee88ccdd19279f8f9268