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FA-67836 / Elevator dispatch scheduling / Open access

Encoder position and door zone detection: millimetre rounding · case 01

Positions just short of the zone edge are rounded into it.

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

ROOT CAUSE

The position is rounded to nearest millimetre instead of floored.

VERIFIED REPAIR

Floor the micrometre position to millimetres.

Unsuccessful approach: Ceiling division rounds every fractional millimetre up.

Case contract

Car position is tracked in micrometres: start_mm*1000, pulses add count*um_per_pulse, a door-zone magnet at floor k resets the position to floor_mm[k]*1000. After every event the position in mm is floor(um/1000); the car is at the nearest floor (ties to the lower index) if within zone_mm inclusive, otherwise None (between floors).

Why this case matters

Lift group controllers make these decisions many times per minute; a wrong answer strands passengers, wastes trips or overrides a safety rule.

1 / The failure

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

N = 1
observations = []
def solve(x):
    table = x['floor_mm']
    pos = x['start_mm'] * 1000
    out = []
    for kind, v in x['events']:
        if kind == 'pulses':
            pos += v * x['um_per_pulse']
        else:
            pos = table[v] * 1000
        mm = round(pos / 1000)
        best = min(range(len(table)), key=lambda k: (abs(table[k] - mm), k))
        out.append(best if abs(table[best] - mm) <= x['zone_mm'] else None)
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[('regression: six-tenths of a millimetre short of the zone', {'floor_mm': [0, 3000], 'start_mm': 2924, 'um_per_pulse': 600, 'zone_mm': 75, 'events': [['pulses', 1], ['pulses', 1]]}, [None, 1]), ('boundary: encoder slip accumulates', {'floor_mm': [0, 3000, 6000], 'start_mm': 0, 'um_per_pulse': 997, 'zone_mm': 50, 'events': [['pulses', 3000], ['pulses', 3000]]}, [1, 2]), ('boundary: magnet correction', {'floor_mm': [0, 3000, 6000], 'start_mm': 0, 'um_per_pulse': 1003, 'zone_mm': 50, 'events': [['pulses', 3000], ['magnet', 1], ['pulses', 3000]]}, [1, 1, 2]), ('boundary: zone edge', {'floor_mm': [0, 3000], 'start_mm': 0, 'um_per_pulse': 1000, 'zone_mm': 75, 'events': [['pulses', 2925], ['pulses', 1]]}, [1, 1]), ('boundary: sub-millimetre pulses', {'floor_mm': [0, 3000], 'start_mm': 0, 'um_per_pulse': 997, 'zone_mm': 50, 'events': [['pulses', 999], ['pulses', 2]]}, [None, None]), ('control 1', {'floor_mm': [0, 4200, 8400, 11400, 14900], 'start_mm': 20, 'um_per_pulse': 1000, 'zone_mm': 50, 'events': [['magnet', 3], ['pulses', 5000], ['magnet', 4], ['pulses', 2999], ['pulses', 4200], ['pulses', 2999], ['magnet', 4]]}, [3, None, 4, None, None, None, 4]), ('control 4', {'floor_mm': [0, 3000, 6500, 10000, 13500, 16500, 20000], 'start_mm': 2990, 'um_per_pulse': 1000, 'zone_mm': 75, 'events': [['pulses', 1000], ['pulses', 100]]}, [None, None]), ('control 7', {'floor_mm': [0, 3500, 7700, 10700, 14200, 17200, 21400], 'start_mm': 2990, 'um_per_pulse': 997, 'zone_mm': 75, 'events': [['magnet', 0], ['pulses', 100], ['pulses', 1000], ['pulses', 100], ['magnet', 2], ['pulses', 3000]]}, [0, None, None, None, 2, 3])], [('regression: six-tenths of a millimetre short of the zone', {'floor_mm': [0, 3000], 'start_mm': 2924, 'um_per_pulse': 600, 'zone_mm': 75, 'events': [['pulses', 1], ['pulses', 1]]}, [None, 1]), ('boundary: zone edge', {'floor_mm': [0, 3000], 'start_mm': 0, 'um_per_pulse': 1000, 'zone_mm': 75, 'events': [['pulses', 2925], ['pulses', 1]]}, [1, 1]), ('boundary: sub-millimetre pulses', {'floor_mm': [0, 3000], 'start_mm': 0, 'um_per_pulse': 997, 'zone_mm': 50, 'events': [['pulses', 999], ['pulses', 2]]}, [None, None]), ('boundary: fractional millimetre below a floor', {'floor_mm': [0, 3000], 'start_mm': 2924, 'um_per_pulse': 1003, 'zone_mm': 75, 'events': [['pulses', 1]]}, [1]), ('boundary: encoder slip accumulates', {'floor_mm': [0, 3000, 6000], 'start_mm': 0, 'um_per_pulse': 997, 'zone_mm': 50, 'events': [['pulses', 3000], ['pulses', 3000]]}, [1, 2]), ('control 12', {'floor_mm': [0, 3000, 6000, 10200, 13200, 17400], 'start_mm': 2990, 'um_per_pulse': 997, 'zone_mm': 75, 'events': [['magnet', 0], ['pulses', 3499], ['pulses', 1000], ['pulses', 3500], ['pulses', 100], ['magnet', 2], ['pulses', 3500]]}, [0, None, None, None, None, 2, None]), ('control 15', {'floor_mm': [0, 3000, 7200, 11400, 15600, 19100], 'start_mm': 0, 'um_per_pulse': 1000, 'zone_mm': 50, 'events': [['pulses', 2999], ['pulses', 3499]]}, [1, None]), ('control 18', {'floor_mm': [0, 3000, 7200, 11400, 15600, 19100], 'start_mm': 0, 'um_per_pulse': 1003, 'zone_mm': 75, 'events': [['pulses', 3499], ['pulses', 3000], ['pulses', 3000]]}, [None, None, None])], [('regression: six-tenths of a millimetre short of the zone', {'floor_mm': [0, 3000], 'start_mm': 2924, 'um_per_pulse': 600, 'zone_mm': 75, 'events': [['pulses', 1], ['pulses', 1]]}, [None, 1]), ('boundary: fractional millimetre below a floor', {'floor_mm': [0, 3000], 'start_mm': 2924, 'um_per_pulse': 1003, 'zone_mm': 75, 'events': [['pulses', 1]]}, [1]), ('boundary: encoder slip accumulates', {'floor_mm': [0, 3000, 6000], 'start_mm': 0, 'um_per_pulse': 997, 'zone_mm': 50, 'events': [['pulses', 3000], ['pulses', 3000]]}, [1, 2]), ('boundary: magnet correction', {'floor_mm': [0, 3000, 6000], 'start_mm': 0, 'um_per_pulse': 1003, 'zone_mm': 50, 'events': [['pulses', 3000], ['magnet', 1], ['pulses', 3000]]}, [1, 1, 2]), ('boundary: zone edge', {'floor_mm': [0, 3000], 'start_mm': 0, 'um_per_pulse': 1000, 'zone_mm': 75, 'events': [['pulses', 2925], ['pulses', 1]]}, [1, 1]), ('control 23', {'floor_mm': [0, 4200, 7700, 11200, 15400, 18400, 22600, 25600, 28600], 'start_mm': 0, 'um_per_pulse': 1003, 'zone_mm': 50, 'events': [['pulses', 3500], ['pulses', 3000]]}, [None, None]), ('control 26', {'floor_mm': [0, 4200, 7200, 11400, 14900, 17900, 21400, 25600], 'start_mm': 0, 'um_per_pulse': 997, 'zone_mm': 75, 'events': [['pulses', 4200], ['pulses', 4200], ['pulses', 3500], ['pulses', 2999], ['pulses', 3499], ['pulses', 2999], ['pulses', 4200]]}, [1, None, None, 4, None, 6, None]), ('control 29', {'floor_mm': [0, 4200, 8400, 12600, 16100, 20300, 23800, 27300], 'start_mm': 20, 'um_per_pulse': 600, 'zone_mm': 50, 'events': [['magnet', 3], ['pulses', 2999], ['pulses', 3499], ['pulses', 5000], ['magnet', 1], ['pulses', 100]]}, [3, None, None, None, 1, None])], [('regression: six-tenths of a millimetre short of the zone', {'floor_mm': [0, 3000], 'start_mm': 2924, 'um_per_pulse': 600, 'zone_mm': 75, 'events': [['pulses', 1], ['pulses', 1]]}, [None, 1]), ('boundary: encoder slip accumulates', {'floor_mm': [0, 3000, 6000], 'start_mm': 0, 'um_per_pulse': 997, 'zone_mm': 50, 'events': [['pulses', 3000], ['pulses', 3000]]}, [1, 2]), ('boundary: magnet correction', {'floor_mm': [0, 3000, 6000], 'start_mm': 0, 'um_per_pulse': 1003, 'zone_mm': 50, 'events': [['pulses', 3000], ['magnet', 1], ['pulses', 3000]]}, [1, 1, 2]), ('boundary: zone edge', {'floor_mm': [0, 3000], 'start_mm': 0, 'um_per_pulse': 1000, 'zone_mm': 75, 'events': [['pulses', 2925], ['pulses', 1]]}, [1, 1]), ('boundary: sub-millimetre pulses', {'floor_mm': [0, 3000], 'start_mm': 0, 'um_per_pulse': 997, 'zone_mm': 50, 'events': [['pulses', 999], ['pulses', 2]]}, [None, None]), ('control 34', {'floor_mm': [0, 4200, 7700, 10700, 14200, 17700, 20700, 23700], 'start_mm': 2990, 'um_per_pulse': 600, 'zone_mm': 50, 'events': [['magnet', 5], ['pulses', 5000]]}, [5, 6]), ('control 37', {'floor_mm': [0, 4200, 7200, 10700, 14200, 17700, 20700], 'start_mm': 20, 'um_per_pulse': 1000, 'zone_mm': 50, 'events': [['pulses', 2999], ['pulses', 1000], ['pulses', 100], ['magnet', 2]]}, [None, None, None, 2]), ('control 40', {'floor_mm': [0, 4200, 7700, 11900, 15400, 19600, 22600, 26800, 29800], 'start_mm': 20, 'um_per_pulse': 1000, 'zone_mm': 50, 'events': [['pulses', 3000], ['magnet', 0], ['magnet', 8], ['pulses', 5000], ['pulses', 3000], ['pulses', 5000], ['magnet', 4]]}, [None, 0, 8, None, None, None, 4])], [('regression: six-tenths of a millimetre short of the zone', {'floor_mm': [0, 3000], 'start_mm': 2924, 'um_per_pulse': 600, 'zone_mm': 75, 'events': [['pulses', 1], ['pulses', 1]]}, [None, 1]), ('boundary: zone edge', {'floor_mm': [0, 3000], 'start_mm': 0, 'um_per_pulse': 1000, 'zone_mm': 75, 'events': [['pulses', 2925], ['pulses', 1]]}, [1, 1]), ('boundary: sub-millimetre pulses', {'floor_mm': [0, 3000], 'start_mm': 0, 'um_per_pulse': 997, 'zone_mm': 50, 'events': [['pulses', 999], ['pulses', 2]]}, [None, None]), ('boundary: fractional millimetre below a floor', {'floor_mm': [0, 3000], 'start_mm': 2924, 'um_per_pulse': 1003, 'zone_mm': 75, 'events': [['pulses', 1]]}, [1]), ('boundary: encoder slip accumulates', {'floor_mm': [0, 3000, 6000], 'start_mm': 0, 'um_per_pulse': 997, 'zone_mm': 50, 'events': [['pulses', 3000], ['pulses', 3000]]}, [1, 2]), ('control 45', {'floor_mm': [0, 3000, 7200, 11400, 15600, 19800, 22800, 26300], 'start_mm': 2990, 'um_per_pulse': 600, 'zone_mm': 75, 'events': [['magnet', 3], ['pulses', 3500], ['pulses', 3500]]}, [3, None, 4]), ('control 48', {'floor_mm': [0, 3000, 6000, 9000, 13200, 16200, 20400, 23400, 26400], 'start_mm': 0, 'um_per_pulse': 1003, 'zone_mm': 50, 'events': [['magnet', 0], ['pulses', 1000], ['magnet', 2]]}, [0, None, 2]), ('control 51', {'floor_mm': [0, 4200, 7200, 10700, 14900, 19100], 'start_mm': 2990, 'um_per_pulse': 1003, 'zone_mm': 50, 'events': [['magnet', 0], ['pulses', 100], ['pulses', 100]]}, [0, None, 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
regression: six-tenths of a millimetre short of the zone[1, 1][None, 1]Failed
boundary: encoder slip accumulates[1, 2][1, 2]Passed
boundary: magnet correction[1, 1, 2][1, 1, 2]Passed
boundary: zone edge[1, 1][1, 1]Passed
boundary: sub-millimetre pulses[None, None][None, None]Passed
control 1[3, None, 4, None, None, None, 4][3, None, 4, None, None, None, 4]Passed
control 4[None, None][None, None]Passed
control 7[0, None, None, None, 2, 3][0, None, None, None, 2, 3]Passed

SHA-256 / c8db4b285b421410351b84e9b89523bc733764e0a8376ba75cd8f3bcb20c2e2e

2 / The unsuccessful fix

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

N = 1
observations = []
def solve(x):
    table = x['floor_mm']
    pos = x['start_mm'] * 1000
    out = []
    for kind, v in x['events']:
        if kind == 'pulses':
            pos += v * x['um_per_pulse']
        else:
            pos = table[v] * 1000
        mm = -(-pos // 1000)
        best = min(range(len(table)), key=lambda k: (abs(table[k] - mm), k))
        out.append(best if abs(table[best] - mm) <= x['zone_mm'] else None)
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[('regression: six-tenths of a millimetre short of the zone', {'floor_mm': [0, 3000], 'start_mm': 2924, 'um_per_pulse': 600, 'zone_mm': 75, 'events': [['pulses', 1], ['pulses', 1]]}, [None, 1]), ('boundary: encoder slip accumulates', {'floor_mm': [0, 3000, 6000], 'start_mm': 0, 'um_per_pulse': 997, 'zone_mm': 50, 'events': [['pulses', 3000], ['pulses', 3000]]}, [1, 2]), ('boundary: magnet correction', {'floor_mm': [0, 3000, 6000], 'start_mm': 0, 'um_per_pulse': 1003, 'zone_mm': 50, 'events': [['pulses', 3000], ['magnet', 1], ['pulses', 3000]]}, [1, 1, 2]), ('boundary: zone edge', {'floor_mm': [0, 3000], 'start_mm': 0, 'um_per_pulse': 1000, 'zone_mm': 75, 'events': [['pulses', 2925], ['pulses', 1]]}, [1, 1]), ('boundary: sub-millimetre pulses', {'floor_mm': [0, 3000], 'start_mm': 0, 'um_per_pulse': 997, 'zone_mm': 50, 'events': [['pulses', 999], ['pulses', 2]]}, [None, None]), ('control 1', {'floor_mm': [0, 4200, 8400, 11400, 14900], 'start_mm': 20, 'um_per_pulse': 1000, 'zone_mm': 50, 'events': [['magnet', 3], ['pulses', 5000], ['magnet', 4], ['pulses', 2999], ['pulses', 4200], ['pulses', 2999], ['magnet', 4]]}, [3, None, 4, None, None, None, 4]), ('control 4', {'floor_mm': [0, 3000, 6500, 10000, 13500, 16500, 20000], 'start_mm': 2990, 'um_per_pulse': 1000, 'zone_mm': 75, 'events': [['pulses', 1000], ['pulses', 100]]}, [None, None]), ('control 7', {'floor_mm': [0, 3500, 7700, 10700, 14200, 17200, 21400], 'start_mm': 2990, 'um_per_pulse': 997, 'zone_mm': 75, 'events': [['magnet', 0], ['pulses', 100], ['pulses', 1000], ['pulses', 100], ['magnet', 2], ['pulses', 3000]]}, [0, None, None, None, 2, 3])], [('regression: six-tenths of a millimetre short of the zone', {'floor_mm': [0, 3000], 'start_mm': 2924, 'um_per_pulse': 600, 'zone_mm': 75, 'events': [['pulses', 1], ['pulses', 1]]}, [None, 1]), ('boundary: zone edge', {'floor_mm': [0, 3000], 'start_mm': 0, 'um_per_pulse': 1000, 'zone_mm': 75, 'events': [['pulses', 2925], ['pulses', 1]]}, [1, 1]), ('boundary: sub-millimetre pulses', {'floor_mm': [0, 3000], 'start_mm': 0, 'um_per_pulse': 997, 'zone_mm': 50, 'events': [['pulses', 999], ['pulses', 2]]}, [None, None]), ('boundary: fractional millimetre below a floor', {'floor_mm': [0, 3000], 'start_mm': 2924, 'um_per_pulse': 1003, 'zone_mm': 75, 'events': [['pulses', 1]]}, [1]), ('boundary: encoder slip accumulates', {'floor_mm': [0, 3000, 6000], 'start_mm': 0, 'um_per_pulse': 997, 'zone_mm': 50, 'events': [['pulses', 3000], ['pulses', 3000]]}, [1, 2]), ('control 12', {'floor_mm': [0, 3000, 6000, 10200, 13200, 17400], 'start_mm': 2990, 'um_per_pulse': 997, 'zone_mm': 75, 'events': [['magnet', 0], ['pulses', 3499], ['pulses', 1000], ['pulses', 3500], ['pulses', 100], ['magnet', 2], ['pulses', 3500]]}, [0, None, None, None, None, 2, None]), ('control 15', {'floor_mm': [0, 3000, 7200, 11400, 15600, 19100], 'start_mm': 0, 'um_per_pulse': 1000, 'zone_mm': 50, 'events': [['pulses', 2999], ['pulses', 3499]]}, [1, None]), ('control 18', {'floor_mm': [0, 3000, 7200, 11400, 15600, 19100], 'start_mm': 0, 'um_per_pulse': 1003, 'zone_mm': 75, 'events': [['pulses', 3499], ['pulses', 3000], ['pulses', 3000]]}, [None, None, None])], [('regression: six-tenths of a millimetre short of the zone', {'floor_mm': [0, 3000], 'start_mm': 2924, 'um_per_pulse': 600, 'zone_mm': 75, 'events': [['pulses', 1], ['pulses', 1]]}, [None, 1]), ('boundary: fractional millimetre below a floor', {'floor_mm': [0, 3000], 'start_mm': 2924, 'um_per_pulse': 1003, 'zone_mm': 75, 'events': [['pulses', 1]]}, [1]), ('boundary: encoder slip accumulates', {'floor_mm': [0, 3000, 6000], 'start_mm': 0, 'um_per_pulse': 997, 'zone_mm': 50, 'events': [['pulses', 3000], ['pulses', 3000]]}, [1, 2]), ('boundary: magnet correction', {'floor_mm': [0, 3000, 6000], 'start_mm': 0, 'um_per_pulse': 1003, 'zone_mm': 50, 'events': [['pulses', 3000], ['magnet', 1], ['pulses', 3000]]}, [1, 1, 2]), ('boundary: zone edge', {'floor_mm': [0, 3000], 'start_mm': 0, 'um_per_pulse': 1000, 'zone_mm': 75, 'events': [['pulses', 2925], ['pulses', 1]]}, [1, 1]), ('control 23', {'floor_mm': [0, 4200, 7700, 11200, 15400, 18400, 22600, 25600, 28600], 'start_mm': 0, 'um_per_pulse': 1003, 'zone_mm': 50, 'events': [['pulses', 3500], ['pulses', 3000]]}, [None, None]), ('control 26', {'floor_mm': [0, 4200, 7200, 11400, 14900, 17900, 21400, 25600], 'start_mm': 0, 'um_per_pulse': 997, 'zone_mm': 75, 'events': [['pulses', 4200], ['pulses', 4200], ['pulses', 3500], ['pulses', 2999], ['pulses', 3499], ['pulses', 2999], ['pulses', 4200]]}, [1, None, None, 4, None, 6, None]), ('control 29', {'floor_mm': [0, 4200, 8400, 12600, 16100, 20300, 23800, 27300], 'start_mm': 20, 'um_per_pulse': 600, 'zone_mm': 50, 'events': [['magnet', 3], ['pulses', 2999], ['pulses', 3499], ['pulses', 5000], ['magnet', 1], ['pulses', 100]]}, [3, None, None, None, 1, None])], [('regression: six-tenths of a millimetre short of the zone', {'floor_mm': [0, 3000], 'start_mm': 2924, 'um_per_pulse': 600, 'zone_mm': 75, 'events': [['pulses', 1], ['pulses', 1]]}, [None, 1]), ('boundary: encoder slip accumulates', {'floor_mm': [0, 3000, 6000], 'start_mm': 0, 'um_per_pulse': 997, 'zone_mm': 50, 'events': [['pulses', 3000], ['pulses', 3000]]}, [1, 2]), ('boundary: magnet correction', {'floor_mm': [0, 3000, 6000], 'start_mm': 0, 'um_per_pulse': 1003, 'zone_mm': 50, 'events': [['pulses', 3000], ['magnet', 1], ['pulses', 3000]]}, [1, 1, 2]), ('boundary: zone edge', {'floor_mm': [0, 3000], 'start_mm': 0, 'um_per_pulse': 1000, 'zone_mm': 75, 'events': [['pulses', 2925], ['pulses', 1]]}, [1, 1]), ('boundary: sub-millimetre pulses', {'floor_mm': [0, 3000], 'start_mm': 0, 'um_per_pulse': 997, 'zone_mm': 50, 'events': [['pulses', 999], ['pulses', 2]]}, [None, None]), ('control 34', {'floor_mm': [0, 4200, 7700, 10700, 14200, 17700, 20700, 23700], 'start_mm': 2990, 'um_per_pulse': 600, 'zone_mm': 50, 'events': [['magnet', 5], ['pulses', 5000]]}, [5, 6]), ('control 37', {'floor_mm': [0, 4200, 7200, 10700, 14200, 17700, 20700], 'start_mm': 20, 'um_per_pulse': 1000, 'zone_mm': 50, 'events': [['pulses', 2999], ['pulses', 1000], ['pulses', 100], ['magnet', 2]]}, [None, None, None, 2]), ('control 40', {'floor_mm': [0, 4200, 7700, 11900, 15400, 19600, 22600, 26800, 29800], 'start_mm': 20, 'um_per_pulse': 1000, 'zone_mm': 50, 'events': [['pulses', 3000], ['magnet', 0], ['magnet', 8], ['pulses', 5000], ['pulses', 3000], ['pulses', 5000], ['magnet', 4]]}, [None, 0, 8, None, None, None, 4])], [('regression: six-tenths of a millimetre short of the zone', {'floor_mm': [0, 3000], 'start_mm': 2924, 'um_per_pulse': 600, 'zone_mm': 75, 'events': [['pulses', 1], ['pulses', 1]]}, [None, 1]), ('boundary: zone edge', {'floor_mm': [0, 3000], 'start_mm': 0, 'um_per_pulse': 1000, 'zone_mm': 75, 'events': [['pulses', 2925], ['pulses', 1]]}, [1, 1]), ('boundary: sub-millimetre pulses', {'floor_mm': [0, 3000], 'start_mm': 0, 'um_per_pulse': 997, 'zone_mm': 50, 'events': [['pulses', 999], ['pulses', 2]]}, [None, None]), ('boundary: fractional millimetre below a floor', {'floor_mm': [0, 3000], 'start_mm': 2924, 'um_per_pulse': 1003, 'zone_mm': 75, 'events': [['pulses', 1]]}, [1]), ('boundary: encoder slip accumulates', {'floor_mm': [0, 3000, 6000], 'start_mm': 0, 'um_per_pulse': 997, 'zone_mm': 50, 'events': [['pulses', 3000], ['pulses', 3000]]}, [1, 2]), ('control 45', {'floor_mm': [0, 3000, 7200, 11400, 15600, 19800, 22800, 26300], 'start_mm': 2990, 'um_per_pulse': 600, 'zone_mm': 75, 'events': [['magnet', 3], ['pulses', 3500], ['pulses', 3500]]}, [3, None, 4]), ('control 48', {'floor_mm': [0, 3000, 6000, 9000, 13200, 16200, 20400, 23400, 26400], 'start_mm': 0, 'um_per_pulse': 1003, 'zone_mm': 50, 'events': [['magnet', 0], ['pulses', 1000], ['magnet', 2]]}, [0, None, 2]), ('control 51', {'floor_mm': [0, 4200, 7200, 10700, 14900, 19100], 'start_mm': 2990, 'um_per_pulse': 1003, 'zone_mm': 50, 'events': [['magnet', 0], ['pulses', 100], ['pulses', 100]]}, [0, None, 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
regression: six-tenths of a millimetre short of the zone[1, 1][None, 1]Failed
boundary: encoder slip accumulates[1, 2][1, 2]Passed
boundary: magnet correction[1, 1, 2][1, 1, 2]Passed
boundary: zone edge[1, 1][1, 1]Passed
boundary: sub-millimetre pulses[None, None][None, None]Passed
control 1[3, None, 4, None, None, None, 4][3, None, 4, None, None, None, 4]Passed
control 4[None, None][None, None]Passed
control 7[0, None, None, None, 2, 3][0, None, None, None, 2, 3]Passed

SHA-256 / 810f56f271e266d60cd84c249216ae74da55deb0cd625c7bb55a5b544ce93073

3 / The verified repair

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

N = 1
observations = []
def solve(x):
    table = x['floor_mm']
    pos = x['start_mm'] * 1000
    out = []
    for kind, v in x['events']:
        if kind == 'pulses':
            pos += v * x['um_per_pulse']
        else:
            pos = table[v] * 1000
        mm = pos // 1000
        best = min(range(len(table)), key=lambda k: (abs(table[k] - mm), k))
        out.append(best if abs(table[best] - mm) <= x['zone_mm'] else None)
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[('regression: six-tenths of a millimetre short of the zone', {'floor_mm': [0, 3000], 'start_mm': 2924, 'um_per_pulse': 600, 'zone_mm': 75, 'events': [['pulses', 1], ['pulses', 1]]}, [None, 1]), ('boundary: encoder slip accumulates', {'floor_mm': [0, 3000, 6000], 'start_mm': 0, 'um_per_pulse': 997, 'zone_mm': 50, 'events': [['pulses', 3000], ['pulses', 3000]]}, [1, 2]), ('boundary: magnet correction', {'floor_mm': [0, 3000, 6000], 'start_mm': 0, 'um_per_pulse': 1003, 'zone_mm': 50, 'events': [['pulses', 3000], ['magnet', 1], ['pulses', 3000]]}, [1, 1, 2]), ('boundary: zone edge', {'floor_mm': [0, 3000], 'start_mm': 0, 'um_per_pulse': 1000, 'zone_mm': 75, 'events': [['pulses', 2925], ['pulses', 1]]}, [1, 1]), ('boundary: sub-millimetre pulses', {'floor_mm': [0, 3000], 'start_mm': 0, 'um_per_pulse': 997, 'zone_mm': 50, 'events': [['pulses', 999], ['pulses', 2]]}, [None, None]), ('control 1', {'floor_mm': [0, 4200, 8400, 11400, 14900], 'start_mm': 20, 'um_per_pulse': 1000, 'zone_mm': 50, 'events': [['magnet', 3], ['pulses', 5000], ['magnet', 4], ['pulses', 2999], ['pulses', 4200], ['pulses', 2999], ['magnet', 4]]}, [3, None, 4, None, None, None, 4]), ('control 4', {'floor_mm': [0, 3000, 6500, 10000, 13500, 16500, 20000], 'start_mm': 2990, 'um_per_pulse': 1000, 'zone_mm': 75, 'events': [['pulses', 1000], ['pulses', 100]]}, [None, None]), ('control 7', {'floor_mm': [0, 3500, 7700, 10700, 14200, 17200, 21400], 'start_mm': 2990, 'um_per_pulse': 997, 'zone_mm': 75, 'events': [['magnet', 0], ['pulses', 100], ['pulses', 1000], ['pulses', 100], ['magnet', 2], ['pulses', 3000]]}, [0, None, None, None, 2, 3])], [('regression: six-tenths of a millimetre short of the zone', {'floor_mm': [0, 3000], 'start_mm': 2924, 'um_per_pulse': 600, 'zone_mm': 75, 'events': [['pulses', 1], ['pulses', 1]]}, [None, 1]), ('boundary: zone edge', {'floor_mm': [0, 3000], 'start_mm': 0, 'um_per_pulse': 1000, 'zone_mm': 75, 'events': [['pulses', 2925], ['pulses', 1]]}, [1, 1]), ('boundary: sub-millimetre pulses', {'floor_mm': [0, 3000], 'start_mm': 0, 'um_per_pulse': 997, 'zone_mm': 50, 'events': [['pulses', 999], ['pulses', 2]]}, [None, None]), ('boundary: fractional millimetre below a floor', {'floor_mm': [0, 3000], 'start_mm': 2924, 'um_per_pulse': 1003, 'zone_mm': 75, 'events': [['pulses', 1]]}, [1]), ('boundary: encoder slip accumulates', {'floor_mm': [0, 3000, 6000], 'start_mm': 0, 'um_per_pulse': 997, 'zone_mm': 50, 'events': [['pulses', 3000], ['pulses', 3000]]}, [1, 2]), ('control 12', {'floor_mm': [0, 3000, 6000, 10200, 13200, 17400], 'start_mm': 2990, 'um_per_pulse': 997, 'zone_mm': 75, 'events': [['magnet', 0], ['pulses', 3499], ['pulses', 1000], ['pulses', 3500], ['pulses', 100], ['magnet', 2], ['pulses', 3500]]}, [0, None, None, None, None, 2, None]), ('control 15', {'floor_mm': [0, 3000, 7200, 11400, 15600, 19100], 'start_mm': 0, 'um_per_pulse': 1000, 'zone_mm': 50, 'events': [['pulses', 2999], ['pulses', 3499]]}, [1, None]), ('control 18', {'floor_mm': [0, 3000, 7200, 11400, 15600, 19100], 'start_mm': 0, 'um_per_pulse': 1003, 'zone_mm': 75, 'events': [['pulses', 3499], ['pulses', 3000], ['pulses', 3000]]}, [None, None, None])], [('regression: six-tenths of a millimetre short of the zone', {'floor_mm': [0, 3000], 'start_mm': 2924, 'um_per_pulse': 600, 'zone_mm': 75, 'events': [['pulses', 1], ['pulses', 1]]}, [None, 1]), ('boundary: fractional millimetre below a floor', {'floor_mm': [0, 3000], 'start_mm': 2924, 'um_per_pulse': 1003, 'zone_mm': 75, 'events': [['pulses', 1]]}, [1]), ('boundary: encoder slip accumulates', {'floor_mm': [0, 3000, 6000], 'start_mm': 0, 'um_per_pulse': 997, 'zone_mm': 50, 'events': [['pulses', 3000], ['pulses', 3000]]}, [1, 2]), ('boundary: magnet correction', {'floor_mm': [0, 3000, 6000], 'start_mm': 0, 'um_per_pulse': 1003, 'zone_mm': 50, 'events': [['pulses', 3000], ['magnet', 1], ['pulses', 3000]]}, [1, 1, 2]), ('boundary: zone edge', {'floor_mm': [0, 3000], 'start_mm': 0, 'um_per_pulse': 1000, 'zone_mm': 75, 'events': [['pulses', 2925], ['pulses', 1]]}, [1, 1]), ('control 23', {'floor_mm': [0, 4200, 7700, 11200, 15400, 18400, 22600, 25600, 28600], 'start_mm': 0, 'um_per_pulse': 1003, 'zone_mm': 50, 'events': [['pulses', 3500], ['pulses', 3000]]}, [None, None]), ('control 26', {'floor_mm': [0, 4200, 7200, 11400, 14900, 17900, 21400, 25600], 'start_mm': 0, 'um_per_pulse': 997, 'zone_mm': 75, 'events': [['pulses', 4200], ['pulses', 4200], ['pulses', 3500], ['pulses', 2999], ['pulses', 3499], ['pulses', 2999], ['pulses', 4200]]}, [1, None, None, 4, None, 6, None]), ('control 29', {'floor_mm': [0, 4200, 8400, 12600, 16100, 20300, 23800, 27300], 'start_mm': 20, 'um_per_pulse': 600, 'zone_mm': 50, 'events': [['magnet', 3], ['pulses', 2999], ['pulses', 3499], ['pulses', 5000], ['magnet', 1], ['pulses', 100]]}, [3, None, None, None, 1, None])], [('regression: six-tenths of a millimetre short of the zone', {'floor_mm': [0, 3000], 'start_mm': 2924, 'um_per_pulse': 600, 'zone_mm': 75, 'events': [['pulses', 1], ['pulses', 1]]}, [None, 1]), ('boundary: encoder slip accumulates', {'floor_mm': [0, 3000, 6000], 'start_mm': 0, 'um_per_pulse': 997, 'zone_mm': 50, 'events': [['pulses', 3000], ['pulses', 3000]]}, [1, 2]), ('boundary: magnet correction', {'floor_mm': [0, 3000, 6000], 'start_mm': 0, 'um_per_pulse': 1003, 'zone_mm': 50, 'events': [['pulses', 3000], ['magnet', 1], ['pulses', 3000]]}, [1, 1, 2]), ('boundary: zone edge', {'floor_mm': [0, 3000], 'start_mm': 0, 'um_per_pulse': 1000, 'zone_mm': 75, 'events': [['pulses', 2925], ['pulses', 1]]}, [1, 1]), ('boundary: sub-millimetre pulses', {'floor_mm': [0, 3000], 'start_mm': 0, 'um_per_pulse': 997, 'zone_mm': 50, 'events': [['pulses', 999], ['pulses', 2]]}, [None, None]), ('control 34', {'floor_mm': [0, 4200, 7700, 10700, 14200, 17700, 20700, 23700], 'start_mm': 2990, 'um_per_pulse': 600, 'zone_mm': 50, 'events': [['magnet', 5], ['pulses', 5000]]}, [5, 6]), ('control 37', {'floor_mm': [0, 4200, 7200, 10700, 14200, 17700, 20700], 'start_mm': 20, 'um_per_pulse': 1000, 'zone_mm': 50, 'events': [['pulses', 2999], ['pulses', 1000], ['pulses', 100], ['magnet', 2]]}, [None, None, None, 2]), ('control 40', {'floor_mm': [0, 4200, 7700, 11900, 15400, 19600, 22600, 26800, 29800], 'start_mm': 20, 'um_per_pulse': 1000, 'zone_mm': 50, 'events': [['pulses', 3000], ['magnet', 0], ['magnet', 8], ['pulses', 5000], ['pulses', 3000], ['pulses', 5000], ['magnet', 4]]}, [None, 0, 8, None, None, None, 4])], [('regression: six-tenths of a millimetre short of the zone', {'floor_mm': [0, 3000], 'start_mm': 2924, 'um_per_pulse': 600, 'zone_mm': 75, 'events': [['pulses', 1], ['pulses', 1]]}, [None, 1]), ('boundary: zone edge', {'floor_mm': [0, 3000], 'start_mm': 0, 'um_per_pulse': 1000, 'zone_mm': 75, 'events': [['pulses', 2925], ['pulses', 1]]}, [1, 1]), ('boundary: sub-millimetre pulses', {'floor_mm': [0, 3000], 'start_mm': 0, 'um_per_pulse': 997, 'zone_mm': 50, 'events': [['pulses', 999], ['pulses', 2]]}, [None, None]), ('boundary: fractional millimetre below a floor', {'floor_mm': [0, 3000], 'start_mm': 2924, 'um_per_pulse': 1003, 'zone_mm': 75, 'events': [['pulses', 1]]}, [1]), ('boundary: encoder slip accumulates', {'floor_mm': [0, 3000, 6000], 'start_mm': 0, 'um_per_pulse': 997, 'zone_mm': 50, 'events': [['pulses', 3000], ['pulses', 3000]]}, [1, 2]), ('control 45', {'floor_mm': [0, 3000, 7200, 11400, 15600, 19800, 22800, 26300], 'start_mm': 2990, 'um_per_pulse': 600, 'zone_mm': 75, 'events': [['magnet', 3], ['pulses', 3500], ['pulses', 3500]]}, [3, None, 4]), ('control 48', {'floor_mm': [0, 3000, 6000, 9000, 13200, 16200, 20400, 23400, 26400], 'start_mm': 0, 'um_per_pulse': 1003, 'zone_mm': 50, 'events': [['magnet', 0], ['pulses', 1000], ['magnet', 2]]}, [0, None, 2]), ('control 51', {'floor_mm': [0, 4200, 7200, 10700, 14900, 19100], 'start_mm': 2990, 'um_per_pulse': 1003, 'zone_mm': 50, 'events': [['magnet', 0], ['pulses', 100], ['pulses', 100]]}, [0, None, 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
regression: six-tenths of a millimetre short of the zone[None, 1][None, 1]Passed
boundary: encoder slip accumulates[1, 2][1, 2]Passed
boundary: magnet correction[1, 1, 2][1, 1, 2]Passed
boundary: zone edge[1, 1][1, 1]Passed
boundary: sub-millimetre pulses[None, None][None, None]Passed
control 1[3, None, 4, None, None, None, 4][3, None, 4, None, None, None, 4]Passed
control 4[None, None][None, None]Passed
control 7[0, None, None, None, 2, 3][0, None, None, None, 2, 3]Passed

SHA-256 / 5421ff20b814b368f4096f6498171a8142117df653899762c712dffbb3cf1961

Verification & scope

Stipulated toy lift-control contract for a bounded teaching model; it makes no claim of conformance to any lift code or vendor dispatcher and omits real safety cases. 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 2026-09-29T14:47:56.567680+00:00.

Case digest / ada39206209a16471d215e8f22c660157a48ec10b24b3bc8660cb4f3f07ba652