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FA-97781 / Knitting and sewing pattern grading / Open access

Top-down raglan setup: increase round count · case 01

The yoke stops one round short of the underarm width.

Verified by executionVariant 1 · 8 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

Increase rounds are floored.

VERIFIED REPAIR

Round the increase count up.

Unsuccessful approach: Dividing by 4 assumes four increases per front per round.

Case contract

neck_sts < 16 -> "error: neck too small". Reserve 4 raglan seam stitches; rem = neck-4; front = rem//3; sleeves share rem - 2*front, each sleeve half of that, and an odd leftover goes to the back (back = front + leftover%2). Each increase round adds 2 to front (and back); rounds = max(0, ceiling((underarm_body_sts//2 - front)/2)). yoke_total = neck + 8*rounds.

Why this case matters

Top-down raglan sweaters split the neck cast-on among front, back, sleeves and seam stitches.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
import math
from fractions import Fraction
N = 1
observations = []
def solve(neck_sts, underarm_body_sts):
    if neck_sts < 16:
        return 'error: neck too small'
    rem = neck_sts - 4
    front = rem // 3
    sleeves_total = rem - 2 * front
    sleeve = sleeves_total // 2
    back = front + sleeves_total % 2
    target = underarm_body_sts // 2
    incs = max(0, (target - front) // 2)
    return {'front': front, 'back': back, 'sleeve': sleeve, 'raglan': 4, 'increase_rounds': incs,
            'yoke_total': neck_sts + 8 * incs}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['standard neck', [100, 200],
   {'back': 32, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 372}],
  ['odd leftover', [101, 180],
   {'back': 33, 'front': 32, 'increase_rounds': 29, 'raglan': 4, 'sleeve': 16, 'yoke_total': 333}],
  ['tiny neck', [12, 100], 'error: neck too small'],
  ['regression: increase round count', [80, 80],
   {'back': 25, 'front': 25, 'increase_rounds': 8, 'raglan': 4, 'sleeve': 13, 'yoke_total': 144}],
  ['repair check: increase round count', [80, 180],
   {'back': 25, 'front': 25, 'increase_rounds': 33, 'raglan': 4, 'sleeve': 13, 'yoke_total': 344}],
  ['generated control 1', [80, 160],
   {'back': 25, 'front': 25, 'increase_rounds': 28, 'raglan': 4, 'sleeve': 13, 'yoke_total': 304}],
  ['generated control 2', [12, 201], 'error: neck too small'],
  ['generated control 3', [80, 201],
   {'back': 25, 'front': 25, 'increase_rounds': 38, 'raglan': 4, 'sleeve': 13, 'yoke_total': 384}]],
 [['odd leftover', [101, 180],
   {'back': 33, 'front': 32, 'increase_rounds': 29, 'raglan': 4, 'sleeve': 16, 'yoke_total': 333}],
  ['tiny neck', [12, 100], 'error: neck too small'],
  ['already wide', [120, 60],
   {'back': 38, 'front': 38, 'increase_rounds': 0, 'raglan': 4, 'sleeve': 20, 'yoke_total': 120}],
  ['regression: increase round count', [110, 220],
   {'back': 35, 'front': 35, 'increase_rounds': 38, 'raglan': 4, 'sleeve': 18, 'yoke_total': 414}],
  ['repair check: increase round count', [88, 201],
   {'back': 28, 'front': 28, 'increase_rounds': 36, 'raglan': 4, 'sleeve': 14, 'yoke_total': 376}],
  ['generated control 1', [12, 160], 'error: neck too small'],
  ['generated control 2', [101, 80],
   {'back': 33, 'front': 32, 'increase_rounds': 4, 'raglan': 4, 'sleeve': 16, 'yoke_total': 133}],
  ['generated control 3', [16, 160],
   {'back': 4, 'front': 4, 'increase_rounds': 38, 'raglan': 4, 'sleeve': 2, 'yoke_total': 320}]],
 [['tiny neck', [12, 100], 'error: neck too small'],
  ['already wide', [120, 60],
   {'back': 38, 'front': 38, 'increase_rounds': 0, 'raglan': 4, 'sleeve': 20, 'yoke_total': 120}],
  ['standard neck', [100, 200],
   {'back': 32, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 372}],
  ['regression: increase round count', [110, 80],
   {'back': 35, 'front': 35, 'increase_rounds': 3, 'raglan': 4, 'sleeve': 18, 'yoke_total': 134}],
  ['repair check: increase round count', [100, 80],
   {'back': 32, 'front': 32, 'increase_rounds': 4, 'raglan': 4, 'sleeve': 16, 'yoke_total': 132}],
  ['generated control 1', [96, 80],
   {'back': 30, 'front': 30, 'increase_rounds': 5, 'raglan': 4, 'sleeve': 16, 'yoke_total': 136}],
  ['generated control 2', [101, 200],
   {'back': 33, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 373}],
  ['generated control 3', [101, 220],
   {'back': 33, 'front': 32, 'increase_rounds': 39, 'raglan': 4, 'sleeve': 16, 'yoke_total': 413}]],
 [['already wide', [120, 60],
   {'back': 38, 'front': 38, 'increase_rounds': 0, 'raglan': 4, 'sleeve': 20, 'yoke_total': 120}],
  ['standard neck', [100, 200],
   {'back': 32, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 372}],
  ['odd leftover', [101, 180],
   {'back': 33, 'front': 32, 'increase_rounds': 29, 'raglan': 4, 'sleeve': 16, 'yoke_total': 333}],
  ['regression: increase round count', [110, 180],
   {'back': 35, 'front': 35, 'increase_rounds': 28, 'raglan': 4, 'sleeve': 18, 'yoke_total': 334}],
  ['repair check: increase round count', [101, 200],
   {'back': 33, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 373}],
  ['generated control 1', [96, 220],
   {'back': 30, 'front': 30, 'increase_rounds': 40, 'raglan': 4, 'sleeve': 16, 'yoke_total': 416}],
  ['generated control 2', [12, 180], 'error: neck too small'],
  ['generated control 3', [96, 60],
   {'back': 30, 'front': 30, 'increase_rounds': 0, 'raglan': 4, 'sleeve': 16, 'yoke_total': 96}]],
 [['standard neck', [100, 200],
   {'back': 32, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 372}],
  ['odd leftover', [101, 180],
   {'back': 33, 'front': 32, 'increase_rounds': 29, 'raglan': 4, 'sleeve': 16, 'yoke_total': 333}],
  ['tiny neck', [12, 100], 'error: neck too small'],
  ['regression: increase round count', [80, 180],
   {'back': 25, 'front': 25, 'increase_rounds': 33, 'raglan': 4, 'sleeve': 13, 'yoke_total': 344}],
  ['repair check: increase round count', [16, 60],
   {'back': 4, 'front': 4, 'increase_rounds': 13, 'raglan': 4, 'sleeve': 2, 'yoke_total': 120}],
  ['generated control 1', [12, 201], 'error: neck too small'],
  ['generated control 2', [12, 220], 'error: neck too small'],
  ['generated control 3', [120, 60],
   {'back': 38, 'front': 38, 'increase_rounds': 0, 'raglan': 4, 'sleeve': 20, 'yoke_total': 120}]]]
for label, args, expected in fixtures[N - 1]:
    check(label, solve(*args), expected)
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 fixtureActualExpectedOutcome
standard neck{'back': 32, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 372}{'back': 32, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 372}Passed
odd leftover{'back': 33, 'front': 32, 'increase_rounds': 29, 'raglan': 4, 'sleeve': 16, 'yoke_total': 333}{'back': 33, 'front': 32, 'increase_rounds': 29, 'raglan': 4, 'sleeve': 16, 'yoke_total': 333}Passed
tiny neckerror: neck too smallerror: neck too smallPassed
regression: increase round count{'back': 25, 'front': 25, 'increase_rounds': 7, 'raglan': 4, 'sleeve': 13, 'yoke_total': 136}{'back': 25, 'front': 25, 'increase_rounds': 8, 'raglan': 4, 'sleeve': 13, 'yoke_total': 144}Failed
repair check: increase round count{'back': 25, 'front': 25, 'increase_rounds': 32, 'raglan': 4, 'sleeve': 13, 'yoke_total': 336}{'back': 25, 'front': 25, 'increase_rounds': 33, 'raglan': 4, 'sleeve': 13, 'yoke_total': 344}Failed
generated control 1{'back': 25, 'front': 25, 'increase_rounds': 27, 'raglan': 4, 'sleeve': 13, 'yoke_total': 296}{'back': 25, 'front': 25, 'increase_rounds': 28, 'raglan': 4, 'sleeve': 13, 'yoke_total': 304}Failed
generated control 2error: neck too smallerror: neck too smallPassed
generated control 3{'back': 25, 'front': 25, 'increase_rounds': 37, 'raglan': 4, 'sleeve': 13, 'yoke_total': 376}{'back': 25, 'front': 25, 'increase_rounds': 38, 'raglan': 4, 'sleeve': 13, 'yoke_total': 384}Failed

SHA-256 / 24c3a89f188a6b66147a459955e1972dd344c53ad5eb8627bf90f22ae618d9aa

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
import math
from fractions import Fraction
N = 1
observations = []
def solve(neck_sts, underarm_body_sts):
    if neck_sts < 16:
        return 'error: neck too small'
    rem = neck_sts - 4
    front = rem // 3
    sleeves_total = rem - 2 * front
    sleeve = sleeves_total // 2
    back = front + sleeves_total % 2
    target = underarm_body_sts // 2
    incs = max(0, math.ceil(Fraction(target - front, 4)))
    return {'front': front, 'back': back, 'sleeve': sleeve, 'raglan': 4, 'increase_rounds': incs,
            'yoke_total': neck_sts + 8 * incs}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['standard neck', [100, 200],
   {'back': 32, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 372}],
  ['odd leftover', [101, 180],
   {'back': 33, 'front': 32, 'increase_rounds': 29, 'raglan': 4, 'sleeve': 16, 'yoke_total': 333}],
  ['tiny neck', [12, 100], 'error: neck too small'],
  ['regression: increase round count', [80, 80],
   {'back': 25, 'front': 25, 'increase_rounds': 8, 'raglan': 4, 'sleeve': 13, 'yoke_total': 144}],
  ['repair check: increase round count', [80, 180],
   {'back': 25, 'front': 25, 'increase_rounds': 33, 'raglan': 4, 'sleeve': 13, 'yoke_total': 344}],
  ['generated control 1', [80, 160],
   {'back': 25, 'front': 25, 'increase_rounds': 28, 'raglan': 4, 'sleeve': 13, 'yoke_total': 304}],
  ['generated control 2', [12, 201], 'error: neck too small'],
  ['generated control 3', [80, 201],
   {'back': 25, 'front': 25, 'increase_rounds': 38, 'raglan': 4, 'sleeve': 13, 'yoke_total': 384}]],
 [['odd leftover', [101, 180],
   {'back': 33, 'front': 32, 'increase_rounds': 29, 'raglan': 4, 'sleeve': 16, 'yoke_total': 333}],
  ['tiny neck', [12, 100], 'error: neck too small'],
  ['already wide', [120, 60],
   {'back': 38, 'front': 38, 'increase_rounds': 0, 'raglan': 4, 'sleeve': 20, 'yoke_total': 120}],
  ['regression: increase round count', [110, 220],
   {'back': 35, 'front': 35, 'increase_rounds': 38, 'raglan': 4, 'sleeve': 18, 'yoke_total': 414}],
  ['repair check: increase round count', [88, 201],
   {'back': 28, 'front': 28, 'increase_rounds': 36, 'raglan': 4, 'sleeve': 14, 'yoke_total': 376}],
  ['generated control 1', [12, 160], 'error: neck too small'],
  ['generated control 2', [101, 80],
   {'back': 33, 'front': 32, 'increase_rounds': 4, 'raglan': 4, 'sleeve': 16, 'yoke_total': 133}],
  ['generated control 3', [16, 160],
   {'back': 4, 'front': 4, 'increase_rounds': 38, 'raglan': 4, 'sleeve': 2, 'yoke_total': 320}]],
 [['tiny neck', [12, 100], 'error: neck too small'],
  ['already wide', [120, 60],
   {'back': 38, 'front': 38, 'increase_rounds': 0, 'raglan': 4, 'sleeve': 20, 'yoke_total': 120}],
  ['standard neck', [100, 200],
   {'back': 32, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 372}],
  ['regression: increase round count', [110, 80],
   {'back': 35, 'front': 35, 'increase_rounds': 3, 'raglan': 4, 'sleeve': 18, 'yoke_total': 134}],
  ['repair check: increase round count', [100, 80],
   {'back': 32, 'front': 32, 'increase_rounds': 4, 'raglan': 4, 'sleeve': 16, 'yoke_total': 132}],
  ['generated control 1', [96, 80],
   {'back': 30, 'front': 30, 'increase_rounds': 5, 'raglan': 4, 'sleeve': 16, 'yoke_total': 136}],
  ['generated control 2', [101, 200],
   {'back': 33, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 373}],
  ['generated control 3', [101, 220],
   {'back': 33, 'front': 32, 'increase_rounds': 39, 'raglan': 4, 'sleeve': 16, 'yoke_total': 413}]],
 [['already wide', [120, 60],
   {'back': 38, 'front': 38, 'increase_rounds': 0, 'raglan': 4, 'sleeve': 20, 'yoke_total': 120}],
  ['standard neck', [100, 200],
   {'back': 32, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 372}],
  ['odd leftover', [101, 180],
   {'back': 33, 'front': 32, 'increase_rounds': 29, 'raglan': 4, 'sleeve': 16, 'yoke_total': 333}],
  ['regression: increase round count', [110, 180],
   {'back': 35, 'front': 35, 'increase_rounds': 28, 'raglan': 4, 'sleeve': 18, 'yoke_total': 334}],
  ['repair check: increase round count', [101, 200],
   {'back': 33, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 373}],
  ['generated control 1', [96, 220],
   {'back': 30, 'front': 30, 'increase_rounds': 40, 'raglan': 4, 'sleeve': 16, 'yoke_total': 416}],
  ['generated control 2', [12, 180], 'error: neck too small'],
  ['generated control 3', [96, 60],
   {'back': 30, 'front': 30, 'increase_rounds': 0, 'raglan': 4, 'sleeve': 16, 'yoke_total': 96}]],
 [['standard neck', [100, 200],
   {'back': 32, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 372}],
  ['odd leftover', [101, 180],
   {'back': 33, 'front': 32, 'increase_rounds': 29, 'raglan': 4, 'sleeve': 16, 'yoke_total': 333}],
  ['tiny neck', [12, 100], 'error: neck too small'],
  ['regression: increase round count', [80, 180],
   {'back': 25, 'front': 25, 'increase_rounds': 33, 'raglan': 4, 'sleeve': 13, 'yoke_total': 344}],
  ['repair check: increase round count', [16, 60],
   {'back': 4, 'front': 4, 'increase_rounds': 13, 'raglan': 4, 'sleeve': 2, 'yoke_total': 120}],
  ['generated control 1', [12, 201], 'error: neck too small'],
  ['generated control 2', [12, 220], 'error: neck too small'],
  ['generated control 3', [120, 60],
   {'back': 38, 'front': 38, 'increase_rounds': 0, 'raglan': 4, 'sleeve': 20, 'yoke_total': 120}]]]
for label, args, expected in fixtures[N - 1]:
    check(label, solve(*args), expected)
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 fixtureActualExpectedOutcome
standard neck{'back': 32, 'front': 32, 'increase_rounds': 17, 'raglan': 4, 'sleeve': 16, 'yoke_total': 236}{'back': 32, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 372}Failed
odd leftover{'back': 33, 'front': 32, 'increase_rounds': 15, 'raglan': 4, 'sleeve': 16, 'yoke_total': 221}{'back': 33, 'front': 32, 'increase_rounds': 29, 'raglan': 4, 'sleeve': 16, 'yoke_total': 333}Failed
tiny neckerror: neck too smallerror: neck too smallPassed
regression: increase round count{'back': 25, 'front': 25, 'increase_rounds': 4, 'raglan': 4, 'sleeve': 13, 'yoke_total': 112}{'back': 25, 'front': 25, 'increase_rounds': 8, 'raglan': 4, 'sleeve': 13, 'yoke_total': 144}Failed
repair check: increase round count{'back': 25, 'front': 25, 'increase_rounds': 17, 'raglan': 4, 'sleeve': 13, 'yoke_total': 216}{'back': 25, 'front': 25, 'increase_rounds': 33, 'raglan': 4, 'sleeve': 13, 'yoke_total': 344}Failed
generated control 1{'back': 25, 'front': 25, 'increase_rounds': 14, 'raglan': 4, 'sleeve': 13, 'yoke_total': 192}{'back': 25, 'front': 25, 'increase_rounds': 28, 'raglan': 4, 'sleeve': 13, 'yoke_total': 304}Failed
generated control 2error: neck too smallerror: neck too smallPassed
generated control 3{'back': 25, 'front': 25, 'increase_rounds': 19, 'raglan': 4, 'sleeve': 13, 'yoke_total': 232}{'back': 25, 'front': 25, 'increase_rounds': 38, 'raglan': 4, 'sleeve': 13, 'yoke_total': 384}Failed

SHA-256 / 00401904a350082c874a67a21f2d7a95ef0343e41fb8551d72dca5082cf52544

3 / The verified repair

Exit 0
"""Failure Map reference implementation. Python standard library only."""
import json
import math
from fractions import Fraction
N = 1
observations = []
def solve(neck_sts, underarm_body_sts):
    if neck_sts < 16:
        return 'error: neck too small'
    rem = neck_sts - 4
    front = rem // 3
    sleeves_total = rem - 2 * front
    sleeve = sleeves_total // 2
    back = front + sleeves_total % 2
    target = underarm_body_sts // 2
    incs = max(0, math.ceil(Fraction(target - front, 2)))
    return {'front': front, 'back': back, 'sleeve': sleeve, 'raglan': 4, 'increase_rounds': incs,
            'yoke_total': neck_sts + 8 * incs}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['standard neck', [100, 200],
   {'back': 32, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 372}],
  ['odd leftover', [101, 180],
   {'back': 33, 'front': 32, 'increase_rounds': 29, 'raglan': 4, 'sleeve': 16, 'yoke_total': 333}],
  ['tiny neck', [12, 100], 'error: neck too small'],
  ['regression: increase round count', [80, 80],
   {'back': 25, 'front': 25, 'increase_rounds': 8, 'raglan': 4, 'sleeve': 13, 'yoke_total': 144}],
  ['repair check: increase round count', [80, 180],
   {'back': 25, 'front': 25, 'increase_rounds': 33, 'raglan': 4, 'sleeve': 13, 'yoke_total': 344}],
  ['generated control 1', [80, 160],
   {'back': 25, 'front': 25, 'increase_rounds': 28, 'raglan': 4, 'sleeve': 13, 'yoke_total': 304}],
  ['generated control 2', [12, 201], 'error: neck too small'],
  ['generated control 3', [80, 201],
   {'back': 25, 'front': 25, 'increase_rounds': 38, 'raglan': 4, 'sleeve': 13, 'yoke_total': 384}]],
 [['odd leftover', [101, 180],
   {'back': 33, 'front': 32, 'increase_rounds': 29, 'raglan': 4, 'sleeve': 16, 'yoke_total': 333}],
  ['tiny neck', [12, 100], 'error: neck too small'],
  ['already wide', [120, 60],
   {'back': 38, 'front': 38, 'increase_rounds': 0, 'raglan': 4, 'sleeve': 20, 'yoke_total': 120}],
  ['regression: increase round count', [110, 220],
   {'back': 35, 'front': 35, 'increase_rounds': 38, 'raglan': 4, 'sleeve': 18, 'yoke_total': 414}],
  ['repair check: increase round count', [88, 201],
   {'back': 28, 'front': 28, 'increase_rounds': 36, 'raglan': 4, 'sleeve': 14, 'yoke_total': 376}],
  ['generated control 1', [12, 160], 'error: neck too small'],
  ['generated control 2', [101, 80],
   {'back': 33, 'front': 32, 'increase_rounds': 4, 'raglan': 4, 'sleeve': 16, 'yoke_total': 133}],
  ['generated control 3', [16, 160],
   {'back': 4, 'front': 4, 'increase_rounds': 38, 'raglan': 4, 'sleeve': 2, 'yoke_total': 320}]],
 [['tiny neck', [12, 100], 'error: neck too small'],
  ['already wide', [120, 60],
   {'back': 38, 'front': 38, 'increase_rounds': 0, 'raglan': 4, 'sleeve': 20, 'yoke_total': 120}],
  ['standard neck', [100, 200],
   {'back': 32, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 372}],
  ['regression: increase round count', [110, 80],
   {'back': 35, 'front': 35, 'increase_rounds': 3, 'raglan': 4, 'sleeve': 18, 'yoke_total': 134}],
  ['repair check: increase round count', [100, 80],
   {'back': 32, 'front': 32, 'increase_rounds': 4, 'raglan': 4, 'sleeve': 16, 'yoke_total': 132}],
  ['generated control 1', [96, 80],
   {'back': 30, 'front': 30, 'increase_rounds': 5, 'raglan': 4, 'sleeve': 16, 'yoke_total': 136}],
  ['generated control 2', [101, 200],
   {'back': 33, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 373}],
  ['generated control 3', [101, 220],
   {'back': 33, 'front': 32, 'increase_rounds': 39, 'raglan': 4, 'sleeve': 16, 'yoke_total': 413}]],
 [['already wide', [120, 60],
   {'back': 38, 'front': 38, 'increase_rounds': 0, 'raglan': 4, 'sleeve': 20, 'yoke_total': 120}],
  ['standard neck', [100, 200],
   {'back': 32, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 372}],
  ['odd leftover', [101, 180],
   {'back': 33, 'front': 32, 'increase_rounds': 29, 'raglan': 4, 'sleeve': 16, 'yoke_total': 333}],
  ['regression: increase round count', [110, 180],
   {'back': 35, 'front': 35, 'increase_rounds': 28, 'raglan': 4, 'sleeve': 18, 'yoke_total': 334}],
  ['repair check: increase round count', [101, 200],
   {'back': 33, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 373}],
  ['generated control 1', [96, 220],
   {'back': 30, 'front': 30, 'increase_rounds': 40, 'raglan': 4, 'sleeve': 16, 'yoke_total': 416}],
  ['generated control 2', [12, 180], 'error: neck too small'],
  ['generated control 3', [96, 60],
   {'back': 30, 'front': 30, 'increase_rounds': 0, 'raglan': 4, 'sleeve': 16, 'yoke_total': 96}]],
 [['standard neck', [100, 200],
   {'back': 32, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 372}],
  ['odd leftover', [101, 180],
   {'back': 33, 'front': 32, 'increase_rounds': 29, 'raglan': 4, 'sleeve': 16, 'yoke_total': 333}],
  ['tiny neck', [12, 100], 'error: neck too small'],
  ['regression: increase round count', [80, 180],
   {'back': 25, 'front': 25, 'increase_rounds': 33, 'raglan': 4, 'sleeve': 13, 'yoke_total': 344}],
  ['repair check: increase round count', [16, 60],
   {'back': 4, 'front': 4, 'increase_rounds': 13, 'raglan': 4, 'sleeve': 2, 'yoke_total': 120}],
  ['generated control 1', [12, 201], 'error: neck too small'],
  ['generated control 2', [12, 220], 'error: neck too small'],
  ['generated control 3', [120, 60],
   {'back': 38, 'front': 38, 'increase_rounds': 0, 'raglan': 4, 'sleeve': 20, 'yoke_total': 120}]]]
for label, args, expected in fixtures[N - 1]:
    check(label, solve(*args), expected)
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 fixtureActualExpectedOutcome
standard neck{'back': 32, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 372}{'back': 32, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 372}Passed
odd leftover{'back': 33, 'front': 32, 'increase_rounds': 29, 'raglan': 4, 'sleeve': 16, 'yoke_total': 333}{'back': 33, 'front': 32, 'increase_rounds': 29, 'raglan': 4, 'sleeve': 16, 'yoke_total': 333}Passed
tiny neckerror: neck too smallerror: neck too smallPassed
regression: increase round count{'back': 25, 'front': 25, 'increase_rounds': 8, 'raglan': 4, 'sleeve': 13, 'yoke_total': 144}{'back': 25, 'front': 25, 'increase_rounds': 8, 'raglan': 4, 'sleeve': 13, 'yoke_total': 144}Passed
repair check: increase round count{'back': 25, 'front': 25, 'increase_rounds': 33, 'raglan': 4, 'sleeve': 13, 'yoke_total': 344}{'back': 25, 'front': 25, 'increase_rounds': 33, 'raglan': 4, 'sleeve': 13, 'yoke_total': 344}Passed
generated control 1{'back': 25, 'front': 25, 'increase_rounds': 28, 'raglan': 4, 'sleeve': 13, 'yoke_total': 304}{'back': 25, 'front': 25, 'increase_rounds': 28, 'raglan': 4, 'sleeve': 13, 'yoke_total': 304}Passed
generated control 2error: neck too smallerror: neck too smallPassed
generated control 3{'back': 25, 'front': 25, 'increase_rounds': 38, 'raglan': 4, 'sleeve': 13, 'yoke_total': 384}{'back': 25, 'front': 25, 'increase_rounds': 38, 'raglan': 4, 'sleeve': 13, 'yoke_total': 384}Passed

SHA-256 / 871b59f9f41a689069fbe1225442ee16a02989e29309f8b033e81bf6d36512e1

Verification & scope

A deterministic toy contract stated in full here; it is a bounded teaching model, not an authoritative reference or standards implementation. 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 2026-09-29T14:52:35.513870+00:00.

Case digest / fd1370ff1ef21c1253623e983e3ef050ac4bffb5bdc9902f64c0dd35db2044f3