FA-5796 / Planar geometry / Open access
Circle area divided by pi · case 01
Circumference scaling is used for an area.
ROOT CAUSE
Circumference scaling is used for an area.
VERIFIED REPAIR
Apply the specified mathematical contract directly, preserving all terms and boundary cases: return radius**2
Unsuccessful approach: The radius is not squared.
Case 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. Circle area divided by pi. Exact operational definition: radius**2
Why this case matters
Small exact fixtures expose this error without platform timing, external services, or probabilistic observations. Planar geometry results depend on the stated convention.
1 / The failure
Exit 1"""Failure Map reference implementation. Python standard library only."""
import json
import math
import calendar
import statistics
import itertools
from fractions import Fraction
from datetime import date, datetime, timedelta, timezone
from decimal import Decimal, ROUND_HALF_UP, ROUND_DOWN, ROUND_CEILING, ROUND_FLOOR
N = 1
observations = []
def solve(radius):
return 2*radius
def check(label, actual, expected):
observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1: (0,)', solve(*(0,)), 0)
check('fixture 2: (1,)', solve(*(1,)), 1)
check('fixture 3: (3,)', solve(*(3,)), 9)
check('fixture 4: (5,)', solve(*(5,)), 25)
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 fixture | Actual | Expected | Outcome |
|---|---|---|---|
| fixture 1: (0,) | 0 | 0 | Passed |
| fixture 2: (1,) | 2 | 1 | Failed |
| fixture 3: (3,) | 6 | 9 | Failed |
| fixture 4: (5,) | 10 | 25 | Failed |
SHA-256 / ecbfa309dca1ea3ec9483c26588ea2208e75dd90a7b4d0912d1bbf8048ee1f81
2 / The unsuccessful fix
Exit 1"""Failure Map reference implementation. Python standard library only."""
import json
import math
import calendar
import statistics
import itertools
from fractions import Fraction
from datetime import date, datetime, timedelta, timezone
from decimal import Decimal, ROUND_HALF_UP, ROUND_DOWN, ROUND_CEILING, ROUND_FLOOR
N = 1
observations = []
def solve(radius):
return radius
def check(label, actual, expected):
observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1: (0,)', solve(*(0,)), 0)
check('fixture 2: (1,)', solve(*(1,)), 1)
check('fixture 3: (3,)', solve(*(3,)), 9)
check('fixture 4: (5,)', solve(*(5,)), 25)
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 fixture | Actual | Expected | Outcome |
|---|---|---|---|
| fixture 1: (0,) | 0 | 0 | Passed |
| fixture 2: (1,) | 1 | 1 | Passed |
| fixture 3: (3,) | 3 | 9 | Failed |
| fixture 4: (5,) | 5 | 25 | Failed |
SHA-256 / 00a1c6eaa5cd29263c24b2f9301995052d8ab6eb37f433e27beb79c105735527
3 / The verified repair
Exit 0"""Failure Map reference implementation. Python standard library only."""
import json
import math
import calendar
import statistics
import itertools
from fractions import Fraction
from datetime import date, datetime, timedelta, timezone
from decimal import Decimal, ROUND_HALF_UP, ROUND_DOWN, ROUND_CEILING, ROUND_FLOOR
N = 1
observations = []
def solve(radius):
return radius**2
def check(label, actual, expected):
observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1: (0,)', solve(*(0,)), 0)
check('fixture 2: (1,)', solve(*(1,)), 1)
check('fixture 3: (3,)', solve(*(3,)), 9)
check('fixture 4: (5,)', solve(*(5,)), 25)
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 fixture | Actual | Expected | Outcome |
|---|---|---|---|
| fixture 1: (0,) | 0 | 0 | Passed |
| fixture 2: (1,) | 1 | 1 | Passed |
| fixture 3: (3,) | 9 | 9 | Passed |
| fixture 4: (5,) | 25 | 25 | Passed |
SHA-256 / 354296b417acdf4a139cea89d3f61271d9fff4090f25af34c592067fe9f0fb36
Verification & scope
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 2026-09-29T14:37:53.638574+00:00.
Case digest / 1cd650c1c6a3213c3f2a4792c2877497a423216a4e975c8f8315eac08717bfd7