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FA-97776 / Knitting and sewing pattern grading / Open access

Top-down raglan setup: odd leftover placement · case 01

An odd neck count loses a stitch in the split.

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

ROOT CAUSE

The odd leftover stitch from the sleeve share is dropped.

VERIFIED REPAIR

Give the odd leftover to the back.

Unsuccessful approach: Always adding one to the back gains a stitch on even splits.

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
    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: odd leftover placement', [101, 201],
   {'back': 33, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 373}],
  ['repair check: odd leftover placement', [16, 201],
   {'back': 4, 'front': 4, 'increase_rounds': 48, 'raglan': 4, 'sleeve': 2, 'yoke_total': 400}],
  ['generated control 1', [88, 80],
   {'back': 28, 'front': 28, 'increase_rounds': 6, 'raglan': 4, 'sleeve': 14, 'yoke_total': 136}],
  ['generated control 2', [88, 200],
   {'back': 28, 'front': 28, 'increase_rounds': 36, 'raglan': 4, 'sleeve': 14, 'yoke_total': 376}],
  ['generated control 3', [96, 160],
   {'back': 30, 'front': 30, 'increase_rounds': 25, 'raglan': 4, 'sleeve': 16, 'yoke_total': 296}]],
 [['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}],
  ['repair check: odd leftover placement', [16, 201],
   {'back': 4, 'front': 4, 'increase_rounds': 48, 'raglan': 4, 'sleeve': 2, 'yoke_total': 400}],
  ['generated control 1', [110, 220],
   {'back': 35, 'front': 35, 'increase_rounds': 38, 'raglan': 4, 'sleeve': 18, 'yoke_total': 414}],
  ['generated control 2', [12, 220], 'error: neck too small'],
  ['generated control 3', [16, 160],
   {'back': 4, 'front': 4, 'increase_rounds': 38, 'raglan': 4, 'sleeve': 2, 'yoke_total': 320}],
  ['generated control 4', [120, 201],
   {'back': 38, 'front': 38, 'increase_rounds': 31, 'raglan': 4, 'sleeve': 20, 'yoke_total': 368}]],
 [['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: odd leftover placement', [101, 200],
   {'back': 33, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 373}],
  ['generated control 1', [120, 200],
   {'back': 38, 'front': 38, 'increase_rounds': 31, 'raglan': 4, 'sleeve': 20, 'yoke_total': 368}],
  ['generated control 2', [16, 60],
   {'back': 4, 'front': 4, 'increase_rounds': 13, 'raglan': 4, 'sleeve': 2, 'yoke_total': 120}],
  ['generated control 3', [80, 80],
   {'back': 25, 'front': 25, 'increase_rounds': 8, 'raglan': 4, 'sleeve': 13, 'yoke_total': 144}],
  ['generated control 4', [120, 180],
   {'back': 38, 'front': 38, 'increase_rounds': 26, 'raglan': 4, 'sleeve': 20, 'yoke_total': 328}]],
 [['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: odd leftover placement', [101, 200],
   {'back': 33, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 373}],
  ['repair check: odd leftover placement', [88, 80],
   {'back': 28, 'front': 28, 'increase_rounds': 6, 'raglan': 4, 'sleeve': 14, 'yoke_total': 136}],
  ['generated control 1', [12, 200], 'error: neck too small'],
  ['generated control 2', [110, 160],
   {'back': 35, 'front': 35, 'increase_rounds': 23, 'raglan': 4, 'sleeve': 18, 'yoke_total': 294}],
  ['generated control 3', [96, 80],
   {'back': 30, 'front': 30, 'increase_rounds': 5, 'raglan': 4, 'sleeve': 16, 'yoke_total': 136}]],
 [['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: odd leftover placement', [101, 200],
   {'back': 33, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 373}],
  ['repair check: odd leftover placement', [100, 180],
   {'back': 32, 'front': 32, 'increase_rounds': 29, 'raglan': 4, 'sleeve': 16, 'yoke_total': 332}],
  ['generated control 1', [100, 160],
   {'back': 32, 'front': 32, 'increase_rounds': 24, 'raglan': 4, 'sleeve': 16, 'yoke_total': 292}],
  ['generated control 2', [120, 220],
   {'back': 38, 'front': 38, 'increase_rounds': 36, 'raglan': 4, 'sleeve': 20, 'yoke_total': 408}],
  ['generated control 3', [12, 60], 'error: neck too small']]]
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': 32, '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}Failed
tiny neckerror: neck too smallerror: neck too smallPassed
regression: odd leftover placement{'back': 32, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 373}{'back': 33, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 373}Failed
repair check: odd leftover placement{'back': 4, 'front': 4, 'increase_rounds': 48, 'raglan': 4, 'sleeve': 2, 'yoke_total': 400}{'back': 4, 'front': 4, 'increase_rounds': 48, 'raglan': 4, 'sleeve': 2, 'yoke_total': 400}Passed
generated control 1{'back': 28, 'front': 28, 'increase_rounds': 6, 'raglan': 4, 'sleeve': 14, 'yoke_total': 136}{'back': 28, 'front': 28, 'increase_rounds': 6, 'raglan': 4, 'sleeve': 14, 'yoke_total': 136}Passed
generated control 2{'back': 28, 'front': 28, 'increase_rounds': 36, 'raglan': 4, 'sleeve': 14, 'yoke_total': 376}{'back': 28, 'front': 28, 'increase_rounds': 36, 'raglan': 4, 'sleeve': 14, 'yoke_total': 376}Passed
generated control 3{'back': 30, 'front': 30, 'increase_rounds': 25, 'raglan': 4, 'sleeve': 16, 'yoke_total': 296}{'back': 30, 'front': 30, 'increase_rounds': 25, 'raglan': 4, 'sleeve': 16, 'yoke_total': 296}Passed

SHA-256 / 93f72b6104ebadc9dc985d39a39184d7b7d252697d3547e9d94ffc35336ce23f

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 + 1
    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: odd leftover placement', [101, 201],
   {'back': 33, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 373}],
  ['repair check: odd leftover placement', [16, 201],
   {'back': 4, 'front': 4, 'increase_rounds': 48, 'raglan': 4, 'sleeve': 2, 'yoke_total': 400}],
  ['generated control 1', [88, 80],
   {'back': 28, 'front': 28, 'increase_rounds': 6, 'raglan': 4, 'sleeve': 14, 'yoke_total': 136}],
  ['generated control 2', [88, 200],
   {'back': 28, 'front': 28, 'increase_rounds': 36, 'raglan': 4, 'sleeve': 14, 'yoke_total': 376}],
  ['generated control 3', [96, 160],
   {'back': 30, 'front': 30, 'increase_rounds': 25, 'raglan': 4, 'sleeve': 16, 'yoke_total': 296}]],
 [['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}],
  ['repair check: odd leftover placement', [16, 201],
   {'back': 4, 'front': 4, 'increase_rounds': 48, 'raglan': 4, 'sleeve': 2, 'yoke_total': 400}],
  ['generated control 1', [110, 220],
   {'back': 35, 'front': 35, 'increase_rounds': 38, 'raglan': 4, 'sleeve': 18, 'yoke_total': 414}],
  ['generated control 2', [12, 220], 'error: neck too small'],
  ['generated control 3', [16, 160],
   {'back': 4, 'front': 4, 'increase_rounds': 38, 'raglan': 4, 'sleeve': 2, 'yoke_total': 320}],
  ['generated control 4', [120, 201],
   {'back': 38, 'front': 38, 'increase_rounds': 31, 'raglan': 4, 'sleeve': 20, 'yoke_total': 368}]],
 [['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: odd leftover placement', [101, 200],
   {'back': 33, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 373}],
  ['generated control 1', [120, 200],
   {'back': 38, 'front': 38, 'increase_rounds': 31, 'raglan': 4, 'sleeve': 20, 'yoke_total': 368}],
  ['generated control 2', [16, 60],
   {'back': 4, 'front': 4, 'increase_rounds': 13, 'raglan': 4, 'sleeve': 2, 'yoke_total': 120}],
  ['generated control 3', [80, 80],
   {'back': 25, 'front': 25, 'increase_rounds': 8, 'raglan': 4, 'sleeve': 13, 'yoke_total': 144}],
  ['generated control 4', [120, 180],
   {'back': 38, 'front': 38, 'increase_rounds': 26, 'raglan': 4, 'sleeve': 20, 'yoke_total': 328}]],
 [['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: odd leftover placement', [101, 200],
   {'back': 33, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 373}],
  ['repair check: odd leftover placement', [88, 80],
   {'back': 28, 'front': 28, 'increase_rounds': 6, 'raglan': 4, 'sleeve': 14, 'yoke_total': 136}],
  ['generated control 1', [12, 200], 'error: neck too small'],
  ['generated control 2', [110, 160],
   {'back': 35, 'front': 35, 'increase_rounds': 23, 'raglan': 4, 'sleeve': 18, 'yoke_total': 294}],
  ['generated control 3', [96, 80],
   {'back': 30, 'front': 30, 'increase_rounds': 5, 'raglan': 4, 'sleeve': 16, 'yoke_total': 136}]],
 [['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: odd leftover placement', [101, 200],
   {'back': 33, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 373}],
  ['repair check: odd leftover placement', [100, 180],
   {'back': 32, 'front': 32, 'increase_rounds': 29, 'raglan': 4, 'sleeve': 16, 'yoke_total': 332}],
  ['generated control 1', [100, 160],
   {'back': 32, 'front': 32, 'increase_rounds': 24, 'raglan': 4, 'sleeve': 16, 'yoke_total': 292}],
  ['generated control 2', [120, 220],
   {'back': 38, 'front': 38, 'increase_rounds': 36, 'raglan': 4, 'sleeve': 20, 'yoke_total': 408}],
  ['generated control 3', [12, 60], 'error: neck too small']]]
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': 33, '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}Failed
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: odd leftover placement{'back': 33, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 373}{'back': 33, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 373}Passed
repair check: odd leftover placement{'back': 5, 'front': 4, 'increase_rounds': 48, 'raglan': 4, 'sleeve': 2, 'yoke_total': 400}{'back': 4, 'front': 4, 'increase_rounds': 48, 'raglan': 4, 'sleeve': 2, 'yoke_total': 400}Failed
generated control 1{'back': 29, 'front': 28, 'increase_rounds': 6, 'raglan': 4, 'sleeve': 14, 'yoke_total': 136}{'back': 28, 'front': 28, 'increase_rounds': 6, 'raglan': 4, 'sleeve': 14, 'yoke_total': 136}Failed
generated control 2{'back': 29, 'front': 28, 'increase_rounds': 36, 'raglan': 4, 'sleeve': 14, 'yoke_total': 376}{'back': 28, 'front': 28, 'increase_rounds': 36, 'raglan': 4, 'sleeve': 14, 'yoke_total': 376}Failed
generated control 3{'back': 31, 'front': 30, 'increase_rounds': 25, 'raglan': 4, 'sleeve': 16, 'yoke_total': 296}{'back': 30, 'front': 30, 'increase_rounds': 25, 'raglan': 4, 'sleeve': 16, 'yoke_total': 296}Failed

SHA-256 / 7e24bd5aa31d092ea0a364a08ccbe3ee6e6e26a239898110cc1a211df8855d2a

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: odd leftover placement', [101, 201],
   {'back': 33, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 373}],
  ['repair check: odd leftover placement', [16, 201],
   {'back': 4, 'front': 4, 'increase_rounds': 48, 'raglan': 4, 'sleeve': 2, 'yoke_total': 400}],
  ['generated control 1', [88, 80],
   {'back': 28, 'front': 28, 'increase_rounds': 6, 'raglan': 4, 'sleeve': 14, 'yoke_total': 136}],
  ['generated control 2', [88, 200],
   {'back': 28, 'front': 28, 'increase_rounds': 36, 'raglan': 4, 'sleeve': 14, 'yoke_total': 376}],
  ['generated control 3', [96, 160],
   {'back': 30, 'front': 30, 'increase_rounds': 25, 'raglan': 4, 'sleeve': 16, 'yoke_total': 296}]],
 [['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}],
  ['repair check: odd leftover placement', [16, 201],
   {'back': 4, 'front': 4, 'increase_rounds': 48, 'raglan': 4, 'sleeve': 2, 'yoke_total': 400}],
  ['generated control 1', [110, 220],
   {'back': 35, 'front': 35, 'increase_rounds': 38, 'raglan': 4, 'sleeve': 18, 'yoke_total': 414}],
  ['generated control 2', [12, 220], 'error: neck too small'],
  ['generated control 3', [16, 160],
   {'back': 4, 'front': 4, 'increase_rounds': 38, 'raglan': 4, 'sleeve': 2, 'yoke_total': 320}],
  ['generated control 4', [120, 201],
   {'back': 38, 'front': 38, 'increase_rounds': 31, 'raglan': 4, 'sleeve': 20, 'yoke_total': 368}]],
 [['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: odd leftover placement', [101, 200],
   {'back': 33, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 373}],
  ['generated control 1', [120, 200],
   {'back': 38, 'front': 38, 'increase_rounds': 31, 'raglan': 4, 'sleeve': 20, 'yoke_total': 368}],
  ['generated control 2', [16, 60],
   {'back': 4, 'front': 4, 'increase_rounds': 13, 'raglan': 4, 'sleeve': 2, 'yoke_total': 120}],
  ['generated control 3', [80, 80],
   {'back': 25, 'front': 25, 'increase_rounds': 8, 'raglan': 4, 'sleeve': 13, 'yoke_total': 144}],
  ['generated control 4', [120, 180],
   {'back': 38, 'front': 38, 'increase_rounds': 26, 'raglan': 4, 'sleeve': 20, 'yoke_total': 328}]],
 [['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: odd leftover placement', [101, 200],
   {'back': 33, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 373}],
  ['repair check: odd leftover placement', [88, 80],
   {'back': 28, 'front': 28, 'increase_rounds': 6, 'raglan': 4, 'sleeve': 14, 'yoke_total': 136}],
  ['generated control 1', [12, 200], 'error: neck too small'],
  ['generated control 2', [110, 160],
   {'back': 35, 'front': 35, 'increase_rounds': 23, 'raglan': 4, 'sleeve': 18, 'yoke_total': 294}],
  ['generated control 3', [96, 80],
   {'back': 30, 'front': 30, 'increase_rounds': 5, 'raglan': 4, 'sleeve': 16, 'yoke_total': 136}]],
 [['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: odd leftover placement', [101, 200],
   {'back': 33, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 373}],
  ['repair check: odd leftover placement', [100, 180],
   {'back': 32, 'front': 32, 'increase_rounds': 29, 'raglan': 4, 'sleeve': 16, 'yoke_total': 332}],
  ['generated control 1', [100, 160],
   {'back': 32, 'front': 32, 'increase_rounds': 24, 'raglan': 4, 'sleeve': 16, 'yoke_total': 292}],
  ['generated control 2', [120, 220],
   {'back': 38, 'front': 38, 'increase_rounds': 36, 'raglan': 4, 'sleeve': 20, 'yoke_total': 408}],
  ['generated control 3', [12, 60], 'error: neck too small']]]
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: odd leftover placement{'back': 33, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 373}{'back': 33, 'front': 32, 'increase_rounds': 34, 'raglan': 4, 'sleeve': 16, 'yoke_total': 373}Passed
repair check: odd leftover placement{'back': 4, 'front': 4, 'increase_rounds': 48, 'raglan': 4, 'sleeve': 2, 'yoke_total': 400}{'back': 4, 'front': 4, 'increase_rounds': 48, 'raglan': 4, 'sleeve': 2, 'yoke_total': 400}Passed
generated control 1{'back': 28, 'front': 28, 'increase_rounds': 6, 'raglan': 4, 'sleeve': 14, 'yoke_total': 136}{'back': 28, 'front': 28, 'increase_rounds': 6, 'raglan': 4, 'sleeve': 14, 'yoke_total': 136}Passed
generated control 2{'back': 28, 'front': 28, 'increase_rounds': 36, 'raglan': 4, 'sleeve': 14, 'yoke_total': 376}{'back': 28, 'front': 28, 'increase_rounds': 36, 'raglan': 4, 'sleeve': 14, 'yoke_total': 376}Passed
generated control 3{'back': 30, 'front': 30, 'increase_rounds': 25, 'raglan': 4, 'sleeve': 16, 'yoke_total': 296}{'back': 30, 'front': 30, 'increase_rounds': 25, 'raglan': 4, 'sleeve': 16, 'yoke_total': 296}Passed

SHA-256 / fa2e4c0b6a4bc5a16adfadf6ca26e368d2c964d43fbffd4fbf08ba892a624148

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 2026-09-29T14:52:35.510237+00:00.

Case digest / 8c46300794327d3b256ea874ec77d9f1e47eb3a39bc69cd4e9c730ec6c53117a