{"abstract":"Configured sign polarity is ignored for a sign-magnitude stream.","category":"PCM sample encoding","checks":8,"contract":"Decode sign-magnitude PCM with configurable physical sign-bit polarity and preserve numerical negative zero as a Boolean sideband.","contract_signature":"codes, width, invert_sign","evaluation_group":"s3-pcm-sign-magnitude-pcm","failed_approach":"OR forces all samples negative when the sign convention is inverted.","family":"s3-pcm-sign-magnitude-pcm-sign-polarity","id":"FA-48946","implementations":{"attempt":{"sha256":"2571f11233482fac275f22706f64ddcf4c5aa2af3b5c2c59dd711c9f1c66db9d","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(codes, width, invert_sign):\n    mask=(1<<(width-1))-1\n    sign=1<<(width-1)\n    values=[]\n    zeros=[]\n    for code in codes:\n        magnitude=code&mask\n        negative=bool(code&sign) or invert_sign\n        values.append(-magnitude if negative else magnitude)\n        zeros.append(bool(negative and magnitude==0))\n    return [values,zeros]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('oracle 1', solve(*([0, 1, 7, 8, 9, 15], 4, False)), [[0, 1, 7, 0, -1, -7], [False, False, False, True, False, False]])\ncheck('oracle 2', solve(*([0, 8, 1, 9], 4, True)), [[0, 0, -1, 1], [True, False, False, False]])\ncheck('oracle 3', solve(*([], 4, False)), [[], []])\ncheck('oracle 4', solve(*([0, 3, 4, 7], 3, False)), [[0, 3, 0, -3], [False, False, True, False]])\ncheck('oracle 5', solve(*([0, 128, 255, 127], 8, False)), [[0, 0, -127, 127], [False, True, False, False]])\ncheck('oracle 6', solve(*([1, 2, 3], 4, True)), [[-1, -2, -3], [False, False, False]])\ncheck('oracle 7', solve(*([0, 4], 3, True)), [[0, 0], [True, False]])\nif N == 1: check('variant packet 1', solve(*[[0, 1, 7, 8, 9, 15, 0, 1, 7, 8, 9, 15], 4, False]), [[0, 1, 7, 0, -1, -7, 0, 1, 7, 0, -1, -7], [False, False, False, True, False, False, False, False, False, True, False, False]])\nif N == 2: check('variant packet 2', solve(*[[0, 1, 7, 8, 9, 15, 0, 1, 7, 8, 9, 15, 0, 1, 7, 8, 9, 15], 4, False]), [[0, 1, 7, 0, -1, -7, 0, 1, 7, 0, -1, -7, 0, 1, 7, 0, -1, -7], [False, False, False, True, False, False, False, False, False, True, False, False, False, False, False, True, False, False]])\nif N == 3: check('variant packet 3', solve(*[[0, 1, 7, 8, 9, 15, 0, 1, 7, 8, 9, 15, 0, 1, 7, 8, 9, 15, 0, 1, 7, 8, 9, 15], 4, False]), [[0, 1, 7, 0, -1, -7, 0, 1, 7, 0, -1, -7, 0, 1, 7, 0, -1, -7, 0, 1, 7, 0, -1, -7], [False, False, False, True, False, False, False, False, False, True, False, False, False, False, False, True, False, False, False, False, False, True, False, False]])\nif N == 4: check('variant packet 4', solve(*[[0, 1, 7, 8, 9, 15, 0, 1, 7, 8, 9, 15, 0, 1, 7, 8, 9, 15, 0, 1, 7, 8, 9, 15, 0, 1, 7, 8, 9, 15], 4, False]), [[0, 1, 7, 0, -1, -7, 0, 1, 7, 0, -1, -7, 0, 1, 7, 0, -1, -7, 0, 1, 7, 0, -1, -7, 0, 1, 7, 0, -1, -7], [False, False, False, True, False, False, False, False, False, True, False, False, False, False, False, True, False, False, False, False, False, True, False, False, False, False, False, True, False, False]])\nif N == 5: check('variant packet 5', solve(*[[0, 1, 7, 8, 9, 15, 0, 1, 7, 8, 9, 15, 0, 1, 7, 8, 9, 15, 0, 1, 7, 8, 9, 15, 0, 1, 7, 8, 9, 15, 0, 1, 7, 8, 9, 15], 4, False]), [[0, 1, 7, 0, -1, -7, 0, 1, 7, 0, -1, -7, 0, 1, 7, 0, -1, -7, 0, 1, 7, 0, -1, -7, 0, 1, 7, 0, -1, -7, 0, 1, 7, 0, -1, -7], [False, False, False, True, False, False, False, False, False, True, False, False, False, False, False, True, False, False, False, False, False, True, False, False, False, False, False, True, False, False, False, False, False, True, False, False]])\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":"1e09568c95184ada188cfbfb6d210fa68c7f14aae98dbe3a2174712371f3f345","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(codes, width, invert_sign):\n    mask=(1<<(width-1))-1\n    sign=1<<(width-1)\n    values=[]\n    zeros=[]\n    for code in codes:\n        magnitude=code&mask\n        negative=bool(code&sign)\n        values.append(-magnitude if negative else magnitude)\n        zeros.append(bool(negative and magnitude==0))\n    return [values,zeros]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('oracle 1', solve(*([0, 1, 7, 8, 9, 15], 4, False)), [[0, 1, 7, 0, -1, -7], [False, False, False, True, False, False]])\ncheck('oracle 2', solve(*([0, 8, 1, 9], 4, True)), [[0, 0, -1, 1], [True, False, False, False]])\ncheck('oracle 3', solve(*([], 4, False)), [[], []])\ncheck('oracle 4', solve(*([0, 3, 4, 7], 3, False)), [[0, 3, 0, -3], [False, False, True, False]])\ncheck('oracle 5', solve(*([0, 128, 255, 127], 8, False)), [[0, 0, -127, 127], [False, True, False, False]])\ncheck('oracle 6', solve(*([1, 2, 3], 4, True)), [[-1, -2, -3], [False, False, False]])\ncheck('oracle 7', solve(*([0, 4], 3, True)), [[0, 0], [True, False]])\nif N == 1: check('variant packet 1', solve(*[[0, 1, 7, 8, 9, 15, 0, 1, 7, 8, 9, 15], 4, False]), [[0, 1, 7, 0, -1, -7, 0, 1, 7, 0, -1, -7], [False, False, False, True, False, False, False, False, False, True, False, False]])\nif N == 2: check('variant packet 2', solve(*[[0, 1, 7, 8, 9, 15, 0, 1, 7, 8, 9, 15, 0, 1, 7, 8, 9, 15], 4, False]), [[0, 1, 7, 0, -1, -7, 0, 1, 7, 0, -1, -7, 0, 1, 7, 0, -1, -7], [False, False, False, True, False, False, False, False, False, True, False, False, False, False, False, True, False, False]])\nif N == 3: check('variant packet 3', solve(*[[0, 1, 7, 8, 9, 15, 0, 1, 7, 8, 9, 15, 0, 1, 7, 8, 9, 15, 0, 1, 7, 8, 9, 15], 4, False]), [[0, 1, 7, 0, -1, -7, 0, 1, 7, 0, -1, -7, 0, 1, 7, 0, -1, -7, 0, 1, 7, 0, -1, -7], [False, False, False, True, False, False, False, False, False, True, False, False, False, False, False, True, False, False, False, False, False, True, False, False]])\nif N == 4: check('variant packet 4', solve(*[[0, 1, 7, 8, 9, 15, 0, 1, 7, 8, 9, 15, 0, 1, 7, 8, 9, 15, 0, 1, 7, 8, 9, 15, 0, 1, 7, 8, 9, 15], 4, False]), [[0, 1, 7, 0, -1, -7, 0, 1, 7, 0, -1, -7, 0, 1, 7, 0, -1, -7, 0, 1, 7, 0, -1, -7, 0, 1, 7, 0, -1, -7], [False, False, False, True, False, False, False, False, False, True, False, False, False, False, False, True, False, False, False, False, False, True, False, False, False, False, False, True, False, False]])\nif N == 5: check('variant packet 5', solve(*[[0, 1, 7, 8, 9, 15, 0, 1, 7, 8, 9, 15, 0, 1, 7, 8, 9, 15, 0, 1, 7, 8, 9, 15, 0, 1, 7, 8, 9, 15, 0, 1, 7, 8, 9, 15], 4, False]), [[0, 1, 7, 0, -1, -7, 0, 1, 7, 0, -1, -7, 0, 1, 7, 0, -1, -7, 0, 1, 7, 0, -1, -7, 0, 1, 7, 0, -1, -7, 0, 1, 7, 0, -1, -7], [False, False, False, True, False, False, False, False, False, True, False, False, False, False, False, True, False, False, False, False, False, True, False, False, False, False, False, True, False, False, False, False, False, True, False, False]])\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":"Stipulated finite model; no claim of hardware timing or full file-format conformance. 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":"s3-pcm-sign-magnitude-pcm-sign-polarity","generated_at":"2026-09-29T14:44:55.571542+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"Offline PCM interchange uses these exact bounded packet and sample representation decisions.","root_cause":"Configured sign polarity is ignored for a sign-magnitude stream.","sha256":"954acab3f3d62e9a192000e6e6ad80ab84d13f50acc97a0331078c5f1a512a3d","title":"Sign magnitude pcm: sign polarity · 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":42.187,"exit_code":1,"observations":[{"actual":[[0,1,7,0,-1,-7],[false,false,false,true,false,false]],"check":"oracle 1","expected":[[0,1,7,0,-1,-7],[false,false,false,true,false,false]],"passed":true},{"actual":[[0,0,-1,-1],[true,true,false,false]],"check":"oracle 2","expected":[[0,0,-1,1],[true,false,false,false]],"passed":false},{"actual":[[],[]],"check":"oracle 3","expected":[[],[]],"passed":true},{"actual":[[0,3,0,-3],[false,false,true,false]],"check":"oracle 4","expected":[[0,3,0,-3],[false,false,true,false]],"passed":true},{"actual":[[0,0,-127,127],[false,true,false,false]],"check":"oracle 5","expected":[[0,0,-127,127],[false,true,false,false]],"passed":true},{"actual":[[-1,-2,-3],[false,false,false]],"check":"oracle 6","expected":[[-1,-2,-3],[false,false,false]],"passed":true},{"actual":[[0,0],[true,true]],"check":"oracle 7","expected":[[0,0],[true,false]],"passed":false},{"actual":[[0,1,7,0,-1,-7,0,1,7,0,-1,-7],[false,false,false,true,false,false,false,false,false,true,false,false]],"check":"variant packet 1","expected":[[0,1,7,0,-1,-7,0,1,7,0,-1,-7],[false,false,false,true,false,false,false,false,false,true,false,false]],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"oracle 1\", \"actual\": [[0, 1, 7, 0, -1, -7], [false, false, false, true, false, false]], \"expected\": [[0, 1, 7, 0, -1, -7], [false, false, false, true, false, false]], \"passed\": true}, {\"check\": \"oracle 2\", \"actual\": [[0, 0, -1, -1], [true, true, false, false]], \"expected\": [[0, 0, -1, 1], [true, false, false, false]], \"passed\": false}, {\"check\": \"oracle 3\", \"actual\": [[], []], \"expected\": [[], []], \"passed\": true}, {\"check\": \"oracle 4\", \"actual\": [[0, 3, 0, -3], [false, false, true, false]], \"expected\": [[0, 3, 0, -3], [false, false, true, false]], \"passed\": true}, {\"check\": \"oracle 5\", \"actual\": [[0, 0, -127, 127], [false, true, false, false]], \"expected\": [[0, 0, -127, 127], [false, true, false, false]], \"passed\": true}, {\"check\": \"oracle 6\", \"actual\": [[-1, -2, -3], [false, false, false]], \"expected\": [[-1, -2, -3], [false, false, false]], \"passed\": true}, {\"check\": \"oracle 7\", \"actual\": [[0, 0], [true, true]], \"expected\": [[0, 0], [true, false]], \"passed\": false}, {\"check\": \"variant packet 1\", \"actual\": [[0, 1, 7, 0, -1, -7, 0, 1, 7, 0, -1, -7], [false, false, false, true, false, false, false, false, false, true, false, false]], \"expected\": [[0, 1, 7, 0, -1, -7, 0, 1, 7, 0, -1, -7], [false, false, false, true, false, false, false, false, false, true, false, false]], \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":40.681,"exit_code":1,"observations":[{"actual":[[0,1,7,0,-1,-7],[false,false,false,true,false,false]],"check":"oracle 1","expected":[[0,1,7,0,-1,-7],[false,false,false,true,false,false]],"passed":true},{"actual":[[0,0,1,-1],[false,true,false,false]],"check":"oracle 2","expected":[[0,0,-1,1],[true,false,false,false]],"passed":false},{"actual":[[],[]],"check":"oracle 3","expected":[[],[]],"passed":true},{"actual":[[0,3,0,-3],[false,false,true,false]],"check":"oracle 4","expected":[[0,3,0,-3],[false,false,true,false]],"passed":true},{"actual":[[0,0,-127,127],[false,true,false,false]],"check":"oracle 5","expected":[[0,0,-127,127],[false,true,false,false]],"passed":true},{"actual":[[1,2,3],[false,false,false]],"check":"oracle 6","expected":[[-1,-2,-3],[false,false,false]],"passed":false},{"actual":[[0,0],[false,true]],"check":"oracle 7","expected":[[0,0],[true,false]],"passed":false},{"actual":[[0,1,7,0,-1,-7,0,1,7,0,-1,-7],[false,false,false,true,false,false,false,false,false,true,false,false]],"check":"variant packet 1","expected":[[0,1,7,0,-1,-7,0,1,7,0,-1,-7],[false,false,false,true,false,false,false,false,false,true,false,false]],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"oracle 1\", \"actual\": [[0, 1, 7, 0, -1, -7], [false, false, false, true, false, false]], \"expected\": [[0, 1, 7, 0, -1, -7], [false, false, false, true, false, false]], \"passed\": true}, {\"check\": \"oracle 2\", \"actual\": [[0, 0, 1, -1], [false, true, false, false]], \"expected\": [[0, 0, -1, 1], [true, false, false, false]], \"passed\": false}, {\"check\": \"oracle 3\", \"actual\": [[], []], \"expected\": [[], []], \"passed\": true}, {\"check\": \"oracle 4\", \"actual\": [[0, 3, 0, -3], [false, false, true, false]], \"expected\": [[0, 3, 0, -3], [false, false, true, false]], \"passed\": true}, {\"check\": \"oracle 5\", \"actual\": [[0, 0, -127, 127], [false, true, false, false]], \"expected\": [[0, 0, -127, 127], [false, true, false, false]], \"passed\": true}, {\"check\": \"oracle 6\", \"actual\": [[1, 2, 3], [false, false, false]], \"expected\": [[-1, -2, -3], [false, false, false]], \"passed\": false}, {\"check\": \"oracle 7\", \"actual\": [[0, 0], [false, true]], \"expected\": [[0, 0], [true, false]], \"passed\": false}, {\"check\": \"variant packet 1\", \"actual\": [[0, 1, 7, 0, -1, -7, 0, 1, 7, 0, -1, -7], [false, false, false, true, false, false, false, false, false, true, false, false]], \"expected\": [[0, 1, 7, 0, -1, -7, 0, 1, 7, 0, -1, -7], [false, false, false, true, false, false, false, false, false, true, false, false]], \"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."}}