{"abstract":"A replacement meter opening register becomes billed energy.","category":"Power metering accounting","checks":6,"contract":"Rows [meter_id, cumulative] are chronological readings. Each meter identifier appears in one contiguous run. Return sum of within-meter consecutive increases; first reading of each meter is a baseline. Readings never decrease within a meter.","evaluation_group":"model-d0b885c19e7f2f94","failed_approach":"Clamping negative cross-meter deltas handles low replacement baselines but bills high replacement baselines.","family":"z-power_metering-replacement-baseline","id":"FA-12286","implementations":{"attempt":{"sha256":"bd050c0c4ce03faeb90e70a5f8635106dd8788612072f59da3780cccdda210f6","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(rows):\n    return sum(max(b[1]-a[1],0) for a,b in zip(rows,rows[1:]))\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('high replacement baseline', solve([['a',N],['a',2*N],['b',100*N],['b',103*N]]),4*N)\ncheck('low replacement baseline', solve([['a',100*N],['a',102*N],['b',0],['b',N]]),3*N)\ncheck('one meter', solve([['a',N],['a',4*N]]),3*N)\ncheck('baseline only', solve([['a',N]]),0)\ncheck('exchange without deltas', solve([['a',N],['b',10*N]]),0)\ncheck('empty', solve([]),0)\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"},"broken":{"sha256":"9d9b3d0c90a25d01c4e55ce86000449475d89244470c87758ca1ab3ecbad148b","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(rows):\n    return rows[-1][1]-rows[0][1] if rows else 0\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('high replacement baseline', solve([['a',N],['a',2*N],['b',100*N],['b',103*N]]),4*N)\ncheck('low replacement baseline', solve([['a',100*N],['a',102*N],['b',0],['b',N]]),3*N)\ncheck('one meter', solve([['a',N],['a',4*N]]),3*N)\ncheck('baseline only', solve([['a',N]]),0)\ncheck('exchange without deltas', solve([['a',N],['b',10*N]]),0)\ncheck('empty', solve([]),0)\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"},"fixed":{"sha256":"b70e710d7cdc1ada918dcb41cc402e88c50d572dbfb5da7cde9ed7fe31e7ac52","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(rows):\n    return sum(b[1]-a[1] for a,b in zip(rows,rows[1:]) if a[0]==b[0])\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('high replacement baseline', solve([['a',N],['a',2*N],['b',100*N],['b',103*N]]),4*N)\ncheck('low replacement baseline', solve([['a',100*N],['a',102*N],['b',0],['b',N]]),3*N)\ncheck('one meter', solve([['a',N],['a',4*N]]),3*N)\ncheck('baseline only', solve([['a',N]]),0)\ncheck('exchange without deltas', solve([['a',N],['b',10*N]]),0)\ncheck('empty', solve([]),0)\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"}},"limitations":"Simplified integer-energy accounting model; no hardware protocol, legal tariff, measurement uncertainty, or live grid behavior is represented. 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.","method":"Deterministic executable model with adversarial boundary fixtures.","provenance":{"created_by":"Failure Map","dependencies":"Python standard library","family":"z-power_metering-replacement-baseline","generated_at":"2026-09-29T14:38:55.550156+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"Meter settlement depends on explicit register and tariff policies; this controlled model makes that policy observable.","repair":"Accumulate deltas only when adjacent readings belong to the same meter.","root_cause":"Subtracting endpoints joins unrelated register origins across a meter exchange.","sha256":"cafd42f029ec1b2f551e08ddc1a964637eb60a3802643a30119fdd969b45beba","title":"A replacement meter opening register becomes billed energy · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verification":{"attempt":{"elapsed_ms":39.413,"exit_code":1,"observations":[{"actual":102,"check":"high replacement baseline","expected":4,"passed":false},{"actual":3,"check":"low replacement baseline","expected":3,"passed":true},{"actual":3,"check":"one meter","expected":3,"passed":true},{"actual":0,"check":"baseline only","expected":0,"passed":true},{"actual":9,"check":"exchange without deltas","expected":0,"passed":false},{"actual":0,"check":"empty","expected":0,"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"high replacement baseline\", \"actual\": 102, \"expected\": 4, \"passed\": false}, {\"check\": \"low replacement baseline\", \"actual\": 3, \"expected\": 3, \"passed\": true}, {\"check\": \"one meter\", \"actual\": 3, \"expected\": 3, \"passed\": true}, {\"check\": \"baseline only\", \"actual\": 0, \"expected\": 0, \"passed\": true}, {\"check\": \"exchange without deltas\", \"actual\": 9, \"expected\": 0, \"passed\": false}, {\"check\": \"empty\", \"actual\": 0, \"expected\": 0, \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":40.721,"exit_code":1,"observations":[{"actual":102,"check":"high replacement baseline","expected":4,"passed":false},{"actual":-99,"check":"low replacement baseline","expected":3,"passed":false},{"actual":3,"check":"one meter","expected":3,"passed":true},{"actual":0,"check":"baseline only","expected":0,"passed":true},{"actual":9,"check":"exchange without deltas","expected":0,"passed":false},{"actual":0,"check":"empty","expected":0,"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"high replacement baseline\", \"actual\": 102, \"expected\": 4, \"passed\": false}, {\"check\": \"low replacement baseline\", \"actual\": -99, \"expected\": 3, \"passed\": false}, {\"check\": \"one meter\", \"actual\": 3, \"expected\": 3, \"passed\": true}, {\"check\": \"baseline only\", \"actual\": 0, \"expected\": 0, \"passed\": true}, {\"check\": \"exchange without deltas\", \"actual\": 9, \"expected\": 0, \"passed\": false}, {\"check\": \"empty\", \"actual\": 0, \"expected\": 0, \"passed\": true}], \"passed\": false}\n"},"fixed":{"elapsed_ms":39.589,"exit_code":0,"observations":[{"actual":4,"check":"high replacement baseline","expected":4,"passed":true},{"actual":3,"check":"low replacement baseline","expected":3,"passed":true},{"actual":3,"check":"one meter","expected":3,"passed":true},{"actual":0,"check":"baseline only","expected":0,"passed":true},{"actual":0,"check":"exchange without deltas","expected":0,"passed":true},{"actual":0,"check":"empty","expected":0,"passed":true}],"passed":true,"stderr":"","stdout":"{\"observations\": [{\"check\": \"high replacement baseline\", \"actual\": 4, \"expected\": 4, \"passed\": true}, {\"check\": \"low replacement baseline\", \"actual\": 3, \"expected\": 3, \"passed\": true}, {\"check\": \"one meter\", \"actual\": 3, \"expected\": 3, \"passed\": true}, {\"check\": \"baseline only\", \"actual\": 0, \"expected\": 0, \"passed\": true}, {\"check\": \"exchange without deltas\", \"actual\": 0, \"expected\": 0, \"passed\": true}, {\"check\": \"empty\", \"actual\": 0, \"expected\": 0, \"passed\": true}], \"passed\": true}\n"}},"verified":true,"visibility":"public"}