{"abstract":"diagonal stride sums both source strides.","category":"Tensor stride and reshape semantics","checks":6,"contract":"A square matrix diagonal view has length min(rows,cols) and stride row_stride+column_stride; preserve offset.","contract_signature":"shape, strides, offset","evaluation_group":"tensor-diagonal-stride","failed_approach":"Summing strides but resetting offset only works for views based at storage origin.","family":"w3-tensor-stride-reshape-diagonal-stride","id":"FA-98801","implementations":{"attempt":{"sha256":"93cd23e5652d7868377e3bce7b05f2d4abf0acc85e43c9067b7f135439e36967","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(shape, strides, offset):\n    return min(shape),strides[0]+strides[1],0\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('row major',solve([N+1,N+1],[N+1,1],6),(N+1,N+2,6))\ncheck('pitched',solve([3,4],[7,2],N),(3,9,N))\ncheck('rectangular',solve([2,5],[10,1],0),(2,11,0))\ncheck('zero stride',solve([N,N],[0,0],4),(N,0,4))\ncheck('negative column',solve([3,3],[3,-1],8),(3,2,8))\ncheck('nonzero origin',solve([1,1],[4,2],N),(1,6,N))\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":"b3e6bdbc141d62be955ff88a3baa16b03d7fcb60c60b25d789ff9a5745b3ffdb","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(shape, strides, offset):\n    return min(shape),strides[0],offset\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('row major',solve([N+1,N+1],[N+1,1],6),(N+1,N+2,6))\ncheck('pitched',solve([3,4],[7,2],N),(3,9,N))\ncheck('rectangular',solve([2,5],[10,1],0),(2,11,0))\ncheck('zero stride',solve([N,N],[0,0],4),(N,0,4))\ncheck('negative column',solve([3,3],[3,-1],8),(3,2,8))\ncheck('nonzero origin',solve([1,1],[4,2],N),(1,6,N))\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":"Self-contained integer metadata models only; no production framework compatibility or performance claim. 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":"w3-tensor-stride-reshape-diagonal-stride","generated_at":"2026-09-30T16:48:17.165359+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"Dense tensor views rely on consistent logical coordinates and physical storage addresses.","root_cause":"Moving one step along the diagonal advances along both source axes.","sha256":"57f90eb8f44ac6a311d8a1bfee95af16a81b6119a3287fdc8374377dc26b034e","title":"Tensor views: diagonal stride sums both source strides · case 01","variant":1,"variant_policy":"The fixture code references N, supplied as 1 through 5. Fixed boundary checks may repeat. These records share one mechanism and must remain together in evaluation splits.","verified":true,"visibility":"public","verification":{"attempt":{"elapsed_ms":28.582,"exit_code":1,"observations":[{"actual":[2,3,0],"check":"row major","expected":[2,3,6],"passed":false},{"actual":[3,9,0],"check":"pitched","expected":[3,9,1],"passed":false},{"actual":[2,11,0],"check":"rectangular","expected":[2,11,0],"passed":true},{"actual":[1,0,0],"check":"zero stride","expected":[1,0,4],"passed":false},{"actual":[3,2,0],"check":"negative column","expected":[3,2,8],"passed":false},{"actual":[1,6,0],"check":"nonzero origin","expected":[1,6,1],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"row major\", \"actual\": [2, 3, 0], \"expected\": [2, 3, 6], \"passed\": false}, {\"check\": \"pitched\", \"actual\": [3, 9, 0], \"expected\": [3, 9, 1], \"passed\": false}, {\"check\": \"rectangular\", \"actual\": [2, 11, 0], \"expected\": [2, 11, 0], \"passed\": true}, {\"check\": \"zero stride\", \"actual\": [1, 0, 0], \"expected\": [1, 0, 4], \"passed\": false}, {\"check\": \"negative column\", \"actual\": [3, 2, 0], \"expected\": [3, 2, 8], \"passed\": false}, {\"check\": \"nonzero origin\", \"actual\": [1, 6, 0], \"expected\": [1, 6, 1], \"passed\": false}], \"passed\": false}\n"},"broken":{"elapsed_ms":29.267,"exit_code":1,"observations":[{"actual":[2,2,6],"check":"row major","expected":[2,3,6],"passed":false},{"actual":[3,7,1],"check":"pitched","expected":[3,9,1],"passed":false},{"actual":[2,10,0],"check":"rectangular","expected":[2,11,0],"passed":false},{"actual":[1,0,4],"check":"zero stride","expected":[1,0,4],"passed":true},{"actual":[3,3,8],"check":"negative column","expected":[3,2,8],"passed":false},{"actual":[1,4,1],"check":"nonzero origin","expected":[1,6,1],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"row major\", \"actual\": [2, 2, 6], \"expected\": [2, 3, 6], \"passed\": false}, {\"check\": \"pitched\", \"actual\": [3, 7, 1], \"expected\": [3, 9, 1], \"passed\": false}, {\"check\": \"rectangular\", \"actual\": [2, 10, 0], \"expected\": [2, 11, 0], \"passed\": false}, {\"check\": \"zero stride\", \"actual\": [1, 0, 4], \"expected\": [1, 0, 4], \"passed\": true}, {\"check\": \"negative column\", \"actual\": [3, 3, 8], \"expected\": [3, 2, 8], \"passed\": false}, {\"check\": \"nonzero origin\", \"actual\": [1, 4, 1], \"expected\": [1, 6, 1], \"passed\": false}], \"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."}}