{"abstract":"Unsigned normalization violates the signed half-open interval.","category":"Planar geometry","checks":4,"contract":"Integer coordinates and lengths, with exact arithmetic except for indicated division results. Lengths are nonnegative. Rectangles are (xmin,ymin,xmax,ymax) with ordered bounds; coordinate vectors have matching dimensions. Degree normalization signed. Exact operational definition: (degrees+180)%360-180","contract_signature":"degrees","evaluation_group":"model-7e714a63a1d99a8f","failed_approach":"Remainder preserves a negative dividend outside the interval.","family":"xn-degree-normalization-signed","id":"FA-5836","implementations":{"attempt":{"sha256":"41ecce2042731e9e1cb6e27250571c84958e3881990dca9ab5b1923192ad5395","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport math\nimport calendar\nimport statistics\nimport itertools\nfrom fractions import Fraction\nfrom datetime import date, datetime, timedelta, timezone\nfrom decimal import Decimal, ROUND_HALF_UP, ROUND_DOWN, ROUND_CEILING, ROUND_FLOOR\n\nN = 1\nobservations = []\ndef solve(degrees):\n    return math.fmod(degrees,360)\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('fixture 1: (180,)', solve(*(180,)), -180)\ncheck('fixture 2: (370,)', solve(*(370,)), 10)\ncheck('fixture 3: (-190,)', solve(*(-190,)), 170)\ncheck('fixture 4: (0,)', solve(*(0,)), 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":"d806ef8b9e8502490338c7c42b1a38a1a39cd4f3bd38b9be2afbf8296b5a6029","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport math\nimport calendar\nimport statistics\nimport itertools\nfrom fractions import Fraction\nfrom datetime import date, datetime, timedelta, timezone\nfrom decimal import Decimal, ROUND_HALF_UP, ROUND_DOWN, ROUND_CEILING, ROUND_FLOOR\n\nN = 1\nobservations = []\ndef solve(degrees):\n    return degrees%360\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('fixture 1: (180,)', solve(*(180,)), -180)\ncheck('fixture 2: (370,)', solve(*(370,)), 10)\ncheck('fixture 3: (-190,)', solve(*(-190,)), 170)\ncheck('fixture 4: (0,)', solve(*(0,)), 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":" 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":"xn-degree-normalization-signed","generated_at":"2026-09-29T14:37:54.383217+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"Small exact fixtures expose this error without platform timing, external services, or probabilistic observations. Planar geometry results depend on the stated convention.","root_cause":"Unsigned normalization violates the signed half-open interval.","sha256":"6e267bdcbe7790b1461516e8ff1fa5371ad3139b49b51d51363818176bf9d025","title":"Degree normalization signed · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verified":true,"visibility":"public","verification":{"attempt":{"elapsed_ms":52.537,"exit_code":1,"observations":[{"actual":180.0,"check":"fixture 1: (180,)","expected":-180,"passed":false},{"actual":10.0,"check":"fixture 2: (370,)","expected":10,"passed":true},{"actual":-190.0,"check":"fixture 3: (-190,)","expected":170,"passed":false},{"actual":0.0,"check":"fixture 4: (0,)","expected":0,"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 1: (180,)\", \"actual\": 180.0, \"expected\": -180, \"passed\": false}, {\"check\": \"fixture 2: (370,)\", \"actual\": 10.0, \"expected\": 10, \"passed\": true}, {\"check\": \"fixture 3: (-190,)\", \"actual\": -190.0, \"expected\": 170, \"passed\": false}, {\"check\": \"fixture 4: (0,)\", \"actual\": 0.0, \"expected\": 0, \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":52.448,"exit_code":1,"observations":[{"actual":180,"check":"fixture 1: (180,)","expected":-180,"passed":false},{"actual":10,"check":"fixture 2: (370,)","expected":10,"passed":true},{"actual":170,"check":"fixture 3: (-190,)","expected":170,"passed":true},{"actual":0,"check":"fixture 4: (0,)","expected":0,"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 1: (180,)\", \"actual\": 180, \"expected\": -180, \"passed\": false}, {\"check\": \"fixture 2: (370,)\", \"actual\": 10, \"expected\": 10, \"passed\": true}, {\"check\": \"fixture 3: (-190,)\", \"actual\": 170, \"expected\": 170, \"passed\": true}, {\"check\": \"fixture 4: (0,)\", \"actual\": 0, \"expected\": 0, \"passed\": true}], \"passed\": false}\n"}},"member_only":{"stages":["fixed"],"fields":["implementations.fixed","verification.fixed","harness","repair"],"note":"The verified repair, its recorded checks, the repair description, and the scoring harness are available to members."}}