FAILURE MAP
← Case archive

FA-92436 / HVAC thermostat control / Open access

Defrost timer accumulates runtime with a dry coil · case 01

The unit defrosts on schedule in dry mild weather even though the coil never got cold enough to frost.

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

ROOT CAUSE

Runtime accumulates whenever the compressor runs, regardless of coil temperature.

VERIFIED REPAIR

Accumulate only while the coil is at or below 32 F.

Unsuccessful approach: Excluding exactly 32 F misses runtime at the freezing point.

Case contract

Heat pump time-temperature defrost sampled per minute (degrees F); samples are [compressor_running, coil_temp, outdoor_temp]. Compressor run minutes accumulate only while coil <= 32. When the accumulation reaches interval and outdoor <= 50, defrost starts that minute and the accumulation resets; otherwise the accumulation keeps growing. Defrost ends on the first later minute with coil >= 57 or when it has lasted max_minutes minutes; that minute reports normal operation. Return heat, off or defrost per minute.

Why this case matters

Residential and light-commercial thermostats make these decisions sample by sample; each defect changes equipment calls in a way that shows up as short cycling, comfort complaints or equipment stress.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(interval, max_minutes, samples):
    acc = 0
    defrost_min = None
    out = []
    for running, coil, outdoor in samples:
        if defrost_min is not None:
            defrost_min += 1
            if coil >= 57 or defrost_min >= max_minutes:
                defrost_min = None
                out.append('heat' if running else 'off')
            else:
                out.append('defrost')
            continue
        if running:
            acc += 1
        if acc >= interval and outdoor <= 50:
            acc = 0
            defrost_min = 0
            out.append('defrost')
            continue
        out.append('heat' if running else 'off')
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['regression: dry coil runtime',
   [2, 3, [[True, 40, 20], [True, 33, 20], [True, 32, 20], [True, 31, 20], [True, 50, 20]]],
   ['heat', 'heat', 'heat', 'defrost', 'defrost']],
  ['regression: two defrosts',
   [3,
    4,
    [[True, 30, 20],
     [True, 30, 20],
     [False, 30, 20],
     [True, 32, 20],
     [True, 40, 20],
     [True, 45, 20],
     [True, 57, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20]]],
   ['heat',
    'heat',
    'off',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'heat',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'heat']],
  ['control: warm outdoor inhibits',
   [2, 3, [[True, 30, 55], [True, 30, 55], [True, 30, 50], [True, 60, 50], [True, 30, 50]]],
   ['heat', 'heat', 'defrost', 'heat', 'heat']],
  ['control: exact termination temperature',
   [1, 5, [[True, 30, 20], [True, 56, 20], [True, 57, 20], [False, 30, 20], [True, 30, 20]]],
   ['defrost', 'defrost', 'heat', 'off', 'defrost']],
  ['regression: scenario 1',
   [3,
    3,
    [[True, 40, 35],
     [True, 40, 50],
     [True, 40, 51],
     [True, 40, 51],
     [True, 40, 50],
     [True, 40, 50],
     [False, 20, 35],
     [False, 20, 51],
     [True, 20, 50],
     [True, 50, 20],
     [True, 50, 50],
     [True, 56, 50],
     [True, 40, 50],
     [True, 40, 50],
     [False, 40, 51],
     [True, 40, 50],
     [False, 20, 51],
     [False, 20, 60],
     [True, 57, 51],
     [False, 57, 51]]],
   ['heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'off',
    'off',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'off',
    'heat',
    'off',
    'off',
    'heat',
    'off']],
  ['regression: scenario 2',
   [4,
    3,
    [[True, 33, 60],
     [False, 57, 20],
     [True, 57, 50],
     [True, 60, 20],
     [True, 60, 35],
     [True, 60, 50],
     [True, 28, 50],
     [True, 28, 20],
     [True, 28, 20],
     [False, 28, 50],
     [True, 28, 51],
     [True, 28, 35],
     [True, 28, 60],
     [True, 28, 50],
     [True, 40, 50],
     [True, 40, 50],
     [False, 40, 60]]],
   ['heat',
    'off',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'off',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'heat',
    'off']],
  ['control: scenario 3',
   [5,
    3,
    [[True, 20, 20],
     [True, 20, 50],
     [True, 20, 50],
     [True, 20, 50],
     [True, 20, 35],
     [True, 40, 50],
     [False, 40, 20],
     [True, 40, 50],
     [True, 40, 50],
     [True, 33, 60],
     [False, 33, 60],
     [True, 60, 50]]],
   ['heat', 'heat', 'heat', 'heat', 'defrost', 'defrost', 'defrost', 'heat', 'heat', 'heat', 'off', 'heat']],
  ['regression: scenario 4',
   [3,
    4,
    [[True, 20, 50],
     [True, 20, 35],
     [True, 20, 60],
     [True, 20, 50],
     [False, 20, 50],
     [True, 20, 35],
     [True, 20, 60],
     [True, 20, 51],
     [False, 20, 20],
     [True, 50, 50],
     [True, 50, 50],
     [False, 50, 50],
     [True, 50, 35],
     [False, 33, 60],
     [True, 33, 60],
     [True, 33, 50],
     [True, 20, 35],
     [True, 20, 35],
     [True, 20, 50],
     [True, 50, 20]]],
   ['heat',
    'heat',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'off',
    'heat',
    'heat',
    'off',
    'heat',
    'off',
    'heat',
    'heat',
    'heat',
    'heat',
    'defrost',
    'defrost']]],
 [['regression: scenario 1',
   [3,
    3,
    [[True, 28, 20],
     [True, 28, 50],
     [True, 32, 50],
     [False, 32, 35],
     [True, 60, 20],
     [True, 60, 35],
     [True, 60, 50],
     [True, 60, 50],
     [True, 57, 50],
     [True, 57, 50],
     [True, 60, 60],
     [False, 60, 50],
     [True, 60, 35],
     [True, 33, 50]]],
   ['heat',
    'heat',
    'defrost',
    'defrost',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'off',
    'heat',
    'heat']],
  ['regression: dry coil runtime',
   [2, 3, [[True, 40, 20], [True, 33, 20], [True, 32, 20], [True, 31, 20], [True, 50, 20]]],
   ['heat', 'heat', 'heat', 'defrost', 'defrost']],
  ['regression: two defrosts',
   [3,
    4,
    [[True, 30, 20],
     [True, 30, 20],
     [False, 30, 20],
     [True, 32, 20],
     [True, 40, 20],
     [True, 45, 20],
     [True, 57, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20]]],
   ['heat',
    'heat',
    'off',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'heat',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'heat']],
  ['control: warm outdoor inhibits',
   [2, 3, [[True, 30, 55], [True, 30, 55], [True, 30, 50], [True, 60, 50], [True, 30, 50]]],
   ['heat', 'heat', 'defrost', 'heat', 'heat']],
  ['control: exact termination temperature',
   [1, 5, [[True, 30, 20], [True, 56, 20], [True, 57, 20], [False, 30, 20], [True, 30, 20]]],
   ['defrost', 'defrost', 'heat', 'off', 'defrost']],
  ['regression: scenario 2',
   [4,
    4,
    [[True, 40, 50],
     [True, 40, 35],
     [True, 40, 60],
     [False, 56, 60],
     [True, 56, 35],
     [True, 50, 50],
     [True, 32, 35],
     [True, 32, 51],
     [True, 32, 20],
     [True, 32, 51],
     [True, 32, 60],
     [True, 57, 35],
     [True, 32, 50],
     [True, 32, 35],
     [True, 20, 35],
     [True, 50, 35],
     [True, 57, 35],
     [True, 57, 51],
     [False, 57, 50]]],
   ['heat',
    'heat',
    'heat',
    'off',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'heat',
    'heat',
    'off']],
  ['regression: scenario 3',
   [3,
    6,
    [[False, 56, 51],
     [True, 56, 35],
     [False, 56, 35],
     [True, 56, 35],
     [True, 56, 35],
     [True, 33, 50],
     [True, 33, 20],
     [True, 33, 50],
     [False, 33, 60],
     [True, 33, 35],
     [True, 33, 35],
     [True, 33, 50],
     [True, 33, 60],
     [True, 33, 35],
     [True, 33, 35],
     [True, 20, 50],
     [True, 20, 51]]],
   ['off',
    'heat',
    'off',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'off',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat']],
  ['regression: scenario 4',
   [4,
    4,
    [[False, 40, 50],
     [True, 40, 50],
     [True, 40, 35],
     [True, 40, 50],
     [True, 40, 50],
     [True, 28, 50],
     [True, 28, 50],
     [False, 28, 60],
     [False, 28, 20],
     [True, 28, 60],
     [True, 28, 50],
     [False, 28, 60],
     [True, 28, 50],
     [True, 28, 35],
     [False, 28, 50],
     [True, 28, 20],
     [True, 28, 51],
     [True, 33, 20]]],
   ['off',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'off',
    'off',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'off',
    'heat',
    'heat',
    'heat']]],
 [['regression: scenario 2',
   [4,
    3,
    [[True, 32, 20],
     [True, 57, 60],
     [True, 57, 60],
     [True, 57, 20],
     [False, 40, 51],
     [True, 50, 50],
     [True, 50, 51],
     [True, 50, 50],
     [True, 56, 60],
     [True, 40, 20],
     [False, 40, 35],
     [True, 50, 35],
     [False, 50, 51],
     [False, 50, 35],
     [True, 57, 35],
     [True, 57, 20],
     [True, 57, 20],
     [True, 57, 50],
     [True, 57, 60]]],
   ['heat',
    'heat',
    'heat',
    'heat',
    'off',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'off',
    'heat',
    'off',
    'off',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat']],
  ['regression: scenario 3',
   [3,
    6,
    [[True, 20, 60],
     [True, 33, 20],
     [True, 33, 60],
     [True, 33, 51],
     [True, 33, 35],
     [True, 32, 50],
     [True, 32, 35],
     [True, 32, 35],
     [True, 32, 60],
     [True, 32, 60],
     [False, 32, 60],
     [True, 32, 35],
     [False, 32, 50],
     [True, 40, 50]]],
   ['heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'off',
    'heat']],
  ['regression: two defrosts',
   [3,
    4,
    [[True, 30, 20],
     [True, 30, 20],
     [False, 30, 20],
     [True, 32, 20],
     [True, 40, 20],
     [True, 45, 20],
     [True, 57, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20]]],
   ['heat',
    'heat',
    'off',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'heat',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'heat']],
  ['control: warm outdoor inhibits',
   [2, 3, [[True, 30, 55], [True, 30, 55], [True, 30, 50], [True, 60, 50], [True, 30, 50]]],
   ['heat', 'heat', 'defrost', 'heat', 'heat']],
  ['regression: dry coil runtime',
   [2, 3, [[True, 40, 20], [True, 33, 20], [True, 32, 20], [True, 31, 20], [True, 50, 20]]],
   ['heat', 'heat', 'heat', 'defrost', 'defrost']],
  ['control: exact termination temperature',
   [1, 5, [[True, 30, 20], [True, 56, 20], [True, 57, 20], [False, 30, 20], [True, 30, 20]]],
   ['defrost', 'defrost', 'heat', 'off', 'defrost']],
  ['regression: scenario 1',
   [4,
    6,
    [[True, 33, 20],
     [True, 28, 50],
     [True, 56, 51],
     [True, 33, 51],
     [True, 28, 35],
     [False, 28, 50],
     [True, 28, 60],
     [True, 28, 20],
     [True, 40, 50],
     [True, 40, 35],
     [True, 40, 51],
     [True, 40, 50],
     [True, 28, 60],
     [True, 28, 50],
     [True, 50, 35],
     [True, 60, 50],
     [True, 57, 20],
     [True, 40, 50]]],
   ['heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'off',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat']],
  ['regression: scenario 4',
   [3,
    3,
    [[True, 28, 51],
     [True, 28, 35],
     [True, 56, 50],
     [False, 56, 51],
     [True, 56, 50],
     [True, 56, 20],
     [False, 40, 50],
     [True, 40, 20],
     [False, 60, 20],
     [True, 50, 50],
     [True, 56, 35],
     [True, 56, 35],
     [True, 56, 51],
     [True, 32, 60],
     [True, 32, 60],
     [True, 32, 35],
     [True, 32, 60],
     [True, 32, 20],
     [True, 32, 50],
     [True, 32, 60],
     [True, 32, 51],
     [True, 40, 20],
     [True, 40, 20],
     [True, 40, 20]]],
   ['heat',
    'heat',
    'heat',
    'off',
    'heat',
    'heat',
    'off',
    'heat',
    'off',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat']]],
 [['regression: scenario 4',
   [4,
    6,
    [[True, 28, 50],
     [True, 28, 35],
     [True, 28, 50],
     [True, 50, 35],
     [True, 40, 50],
     [True, 40, 51],
     [False, 40, 35],
     [True, 20, 50],
     [True, 20, 35],
     [True, 28, 50],
     [True, 32, 51],
     [True, 32, 51],
     [True, 28, 51],
     [False, 28, 50]]],
   ['heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'off',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'off']],
  ['regression: scenario 13',
   [4,
    4,
    [[True, 20, 51],
     [True, 20, 50],
     [True, 32, 20],
     [True, 56, 35],
     [True, 56, 50],
     [True, 56, 51],
     [True, 56, 50],
     [True, 56, 20],
     [True, 32, 20],
     [True, 32, 51],
     [True, 32, 60],
     [True, 33, 51],
     [True, 28, 60],
     [True, 28, 50],
     [True, 28, 50],
     [True, 28, 51],
     [True, 28, 50],
     [True, 28, 51]]],
   ['heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'heat',
    'heat',
    'heat',
    'defrost',
    'defrost']],
  ['regression: two defrosts',
   [3,
    4,
    [[True, 30, 20],
     [True, 30, 20],
     [False, 30, 20],
     [True, 32, 20],
     [True, 40, 20],
     [True, 45, 20],
     [True, 57, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20]]],
   ['heat',
    'heat',
    'off',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'heat',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'heat']],
  ['control: warm outdoor inhibits',
   [2, 3, [[True, 30, 55], [True, 30, 55], [True, 30, 50], [True, 60, 50], [True, 30, 50]]],
   ['heat', 'heat', 'defrost', 'heat', 'heat']],
  ['regression: dry coil runtime',
   [2, 3, [[True, 40, 20], [True, 33, 20], [True, 32, 20], [True, 31, 20], [True, 50, 20]]],
   ['heat', 'heat', 'heat', 'defrost', 'defrost']],
  ['control: exact termination temperature',
   [1, 5, [[True, 30, 20], [True, 56, 20], [True, 57, 20], [False, 30, 20], [True, 30, 20]]],
   ['defrost', 'defrost', 'heat', 'off', 'defrost']],
  ['regression: scenario 1',
   [5,
    4,
    [[True, 57, 60],
     [True, 57, 50],
     [True, 57, 50],
     [True, 57, 35],
     [True, 33, 50],
     [True, 33, 50],
     [True, 32, 50],
     [True, 50, 51],
     [True, 50, 51],
     [False, 50, 20],
     [False, 33, 50],
     [True, 56, 20],
     [True, 32, 60],
     [True, 32, 35],
     [True, 32, 20]]],
   ['heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'off',
    'off',
    'heat',
    'heat',
    'heat',
    'heat']],
  ['regression: scenario 2',
   [4,
    6,
    [[False, 28, 50],
     [True, 28, 51],
     [True, 28, 35],
     [True, 28, 50],
     [True, 57, 50],
     [True, 57, 20],
     [True, 57, 50],
     [True, 57, 50],
     [True, 56, 50],
     [True, 56, 35],
     [True, 56, 51],
     [True, 56, 50]]],
   ['off', 'heat', 'heat', 'heat', 'heat', 'heat', 'heat', 'heat', 'heat', 'heat', 'heat', 'heat']]],
 [['regression: scenario 4',
   [5,
    4,
    [[True, 28, 50],
     [True, 28, 35],
     [True, 28, 50],
     [True, 57, 51],
     [True, 57, 50],
     [True, 57, 20],
     [True, 57, 35],
     [True, 57, 20],
     [True, 57, 35],
     [True, 56, 20],
     [False, 56, 20],
     [True, 33, 35],
     [True, 33, 60],
     [True, 33, 50],
     [True, 20, 50]]],
   ['heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'off',
    'heat',
    'heat',
    'heat',
    'heat']],
  ['regression: scenario 6',
   [4,
    4,
    [[True, 40, 51],
     [True, 40, 20],
     [False, 40, 35],
     [True, 28, 51],
     [True, 28, 20],
     [True, 28, 60],
     [False, 28, 51],
     [False, 28, 51],
     [False, 32, 60],
     [True, 32, 35],
     [True, 20, 51],
     [True, 20, 35],
     [True, 20, 50],
     [True, 20, 20],
     [False, 20, 35]]],
   ['heat',
    'heat',
    'off',
    'heat',
    'heat',
    'heat',
    'off',
    'off',
    'off',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'off']],
  ['regression: two defrosts',
   [3,
    4,
    [[True, 30, 20],
     [True, 30, 20],
     [False, 30, 20],
     [True, 32, 20],
     [True, 40, 20],
     [True, 45, 20],
     [True, 57, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20]]],
   ['heat',
    'heat',
    'off',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'heat',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'heat']],
  ['control: warm outdoor inhibits',
   [2, 3, [[True, 30, 55], [True, 30, 55], [True, 30, 50], [True, 60, 50], [True, 30, 50]]],
   ['heat', 'heat', 'defrost', 'heat', 'heat']],
  ['regression: dry coil runtime',
   [2, 3, [[True, 40, 20], [True, 33, 20], [True, 32, 20], [True, 31, 20], [True, 50, 20]]],
   ['heat', 'heat', 'heat', 'defrost', 'defrost']],
  ['control: exact termination temperature',
   [1, 5, [[True, 30, 20], [True, 56, 20], [True, 57, 20], [False, 30, 20], [True, 30, 20]]],
   ['defrost', 'defrost', 'heat', 'off', 'defrost']],
  ['regression: scenario 1',
   [4,
    6,
    [[True, 32, 50],
     [True, 50, 50],
     [True, 50, 35],
     [True, 57, 51],
     [True, 57, 20],
     [False, 57, 51],
     [True, 57, 50],
     [True, 57, 51],
     [True, 32, 50],
     [True, 32, 51],
     [True, 32, 50],
     [False, 28, 50]]],
   ['heat', 'heat', 'heat', 'heat', 'heat', 'off', 'heat', 'heat', 'heat', 'heat', 'defrost', 'defrost']],
  ['regression: scenario 2',
   [3,
    4,
    [[True, 32, 35],
     [True, 32, 35],
     [True, 33, 60],
     [True, 33, 50],
     [True, 33, 60],
     [True, 57, 51],
     [True, 20, 60],
     [True, 20, 50],
     [True, 33, 50],
     [False, 33, 51],
     [False, 33, 20],
     [True, 33, 20],
     [True, 40, 50],
     [True, 40, 50],
     [True, 40, 35],
     [True, 40, 35],
     [True, 40, 51],
     [True, 28, 35],
     [True, 28, 51],
     [True, 33, 60],
     [False, 33, 60],
     [True, 56, 51],
     [True, 56, 60],
     [False, 56, 60]]],
   ['heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'off',
    'heat',
    'heat',
    'off']]]]
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
regression: dry coil runtime['heat', 'defrost', 'defrost', 'defrost', 'heat']['heat', 'heat', 'heat', 'defrost', 'defrost']Failed
regression: two defrosts['heat', 'heat', 'off', 'defrost', 'defrost', 'defrost', 'heat', 'heat', 'heat', 'defrost', 'defrost', 'defrost', 'defrost', 'heat']['heat', 'heat', 'off', 'defrost', 'defrost', 'defrost', 'heat', 'heat', 'heat', 'defrost', 'defrost', 'defrost', 'defrost', 'heat']Passed
control: warm outdoor inhibits['heat', 'heat', 'defrost', 'heat', 'heat']['heat', 'heat', 'defrost', 'heat', 'heat']Passed
control: exact termination temperature['defrost', 'defrost', 'heat', 'off', 'defrost']['defrost', 'defrost', 'heat', 'off', 'defrost']Passed
regression: scenario 1['heat', 'heat', 'heat', 'heat', 'defrost', 'defrost', 'defrost', 'off', 'heat', 'heat', 'defrost', 'defrost', 'defrost', 'heat', 'off', 'heat', 'off', 'off', 'heat', 'off']['heat', 'heat', 'heat', 'heat', 'heat', 'heat', 'off', 'off', 'heat', 'heat', 'heat', 'heat', 'heat', 'heat', 'off', 'heat', 'off', 'off', 'heat', 'off']Failed
regression: scenario 2['heat', 'off', 'heat', 'heat', 'defrost', 'heat', 'heat', 'heat', 'heat', 'off', 'heat', 'defrost', 'defrost', 'defrost', 'heat', 'heat', 'off']['heat', 'off', 'heat', 'heat', 'heat', 'heat', 'heat', 'heat', 'heat', 'off', 'heat', 'defrost', 'defrost', 'defrost', 'heat', 'heat', 'off']Failed
control: scenario 3['heat', 'heat', 'heat', 'heat', 'defrost', 'defrost', 'defrost', 'heat', 'heat', 'heat', 'off', 'heat']['heat', 'heat', 'heat', 'heat', 'defrost', 'defrost', 'defrost', 'heat', 'heat', 'heat', 'off', 'heat']Passed
regression: scenario 4['heat', 'heat', 'heat', 'defrost', 'defrost', 'defrost', 'defrost', 'heat', 'off', 'heat', 'heat', 'off', 'defrost', 'defrost', 'defrost', 'defrost', 'heat', 'heat', 'heat', 'defrost']['heat', 'heat', 'heat', 'defrost', 'defrost', 'defrost', 'defrost', 'heat', 'off', 'heat', 'heat', 'off', 'heat', 'off', 'heat', 'heat', 'heat', 'heat', 'defrost', 'defrost']Failed

SHA-256 / 9eb34145555ed01e2e30c2625d6d5c903e6b27c0f4badfc7b41c28d93c7354b2

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(interval, max_minutes, samples):
    acc = 0
    defrost_min = None
    out = []
    for running, coil, outdoor in samples:
        if defrost_min is not None:
            defrost_min += 1
            if coil >= 57 or defrost_min >= max_minutes:
                defrost_min = None
                out.append('heat' if running else 'off')
            else:
                out.append('defrost')
            continue
        if running and coil < 32:
            acc += 1
        if acc >= interval and outdoor <= 50:
            acc = 0
            defrost_min = 0
            out.append('defrost')
            continue
        out.append('heat' if running else 'off')
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['regression: dry coil runtime',
   [2, 3, [[True, 40, 20], [True, 33, 20], [True, 32, 20], [True, 31, 20], [True, 50, 20]]],
   ['heat', 'heat', 'heat', 'defrost', 'defrost']],
  ['regression: two defrosts',
   [3,
    4,
    [[True, 30, 20],
     [True, 30, 20],
     [False, 30, 20],
     [True, 32, 20],
     [True, 40, 20],
     [True, 45, 20],
     [True, 57, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20]]],
   ['heat',
    'heat',
    'off',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'heat',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'heat']],
  ['control: warm outdoor inhibits',
   [2, 3, [[True, 30, 55], [True, 30, 55], [True, 30, 50], [True, 60, 50], [True, 30, 50]]],
   ['heat', 'heat', 'defrost', 'heat', 'heat']],
  ['control: exact termination temperature',
   [1, 5, [[True, 30, 20], [True, 56, 20], [True, 57, 20], [False, 30, 20], [True, 30, 20]]],
   ['defrost', 'defrost', 'heat', 'off', 'defrost']],
  ['regression: scenario 1',
   [3,
    3,
    [[True, 40, 35],
     [True, 40, 50],
     [True, 40, 51],
     [True, 40, 51],
     [True, 40, 50],
     [True, 40, 50],
     [False, 20, 35],
     [False, 20, 51],
     [True, 20, 50],
     [True, 50, 20],
     [True, 50, 50],
     [True, 56, 50],
     [True, 40, 50],
     [True, 40, 50],
     [False, 40, 51],
     [True, 40, 50],
     [False, 20, 51],
     [False, 20, 60],
     [True, 57, 51],
     [False, 57, 51]]],
   ['heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'off',
    'off',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'off',
    'heat',
    'off',
    'off',
    'heat',
    'off']],
  ['regression: scenario 2',
   [4,
    3,
    [[True, 33, 60],
     [False, 57, 20],
     [True, 57, 50],
     [True, 60, 20],
     [True, 60, 35],
     [True, 60, 50],
     [True, 28, 50],
     [True, 28, 20],
     [True, 28, 20],
     [False, 28, 50],
     [True, 28, 51],
     [True, 28, 35],
     [True, 28, 60],
     [True, 28, 50],
     [True, 40, 50],
     [True, 40, 50],
     [False, 40, 60]]],
   ['heat',
    'off',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'off',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'heat',
    'off']],
  ['control: scenario 3',
   [5,
    3,
    [[True, 20, 20],
     [True, 20, 50],
     [True, 20, 50],
     [True, 20, 50],
     [True, 20, 35],
     [True, 40, 50],
     [False, 40, 20],
     [True, 40, 50],
     [True, 40, 50],
     [True, 33, 60],
     [False, 33, 60],
     [True, 60, 50]]],
   ['heat', 'heat', 'heat', 'heat', 'defrost', 'defrost', 'defrost', 'heat', 'heat', 'heat', 'off', 'heat']],
  ['regression: scenario 4',
   [3,
    4,
    [[True, 20, 50],
     [True, 20, 35],
     [True, 20, 60],
     [True, 20, 50],
     [False, 20, 50],
     [True, 20, 35],
     [True, 20, 60],
     [True, 20, 51],
     [False, 20, 20],
     [True, 50, 50],
     [True, 50, 50],
     [False, 50, 50],
     [True, 50, 35],
     [False, 33, 60],
     [True, 33, 60],
     [True, 33, 50],
     [True, 20, 35],
     [True, 20, 35],
     [True, 20, 50],
     [True, 50, 20]]],
   ['heat',
    'heat',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'off',
    'heat',
    'heat',
    'off',
    'heat',
    'off',
    'heat',
    'heat',
    'heat',
    'heat',
    'defrost',
    'defrost']]],
 [['regression: scenario 1',
   [3,
    3,
    [[True, 28, 20],
     [True, 28, 50],
     [True, 32, 50],
     [False, 32, 35],
     [True, 60, 20],
     [True, 60, 35],
     [True, 60, 50],
     [True, 60, 50],
     [True, 57, 50],
     [True, 57, 50],
     [True, 60, 60],
     [False, 60, 50],
     [True, 60, 35],
     [True, 33, 50]]],
   ['heat',
    'heat',
    'defrost',
    'defrost',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'off',
    'heat',
    'heat']],
  ['regression: dry coil runtime',
   [2, 3, [[True, 40, 20], [True, 33, 20], [True, 32, 20], [True, 31, 20], [True, 50, 20]]],
   ['heat', 'heat', 'heat', 'defrost', 'defrost']],
  ['regression: two defrosts',
   [3,
    4,
    [[True, 30, 20],
     [True, 30, 20],
     [False, 30, 20],
     [True, 32, 20],
     [True, 40, 20],
     [True, 45, 20],
     [True, 57, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20]]],
   ['heat',
    'heat',
    'off',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'heat',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'heat']],
  ['control: warm outdoor inhibits',
   [2, 3, [[True, 30, 55], [True, 30, 55], [True, 30, 50], [True, 60, 50], [True, 30, 50]]],
   ['heat', 'heat', 'defrost', 'heat', 'heat']],
  ['control: exact termination temperature',
   [1, 5, [[True, 30, 20], [True, 56, 20], [True, 57, 20], [False, 30, 20], [True, 30, 20]]],
   ['defrost', 'defrost', 'heat', 'off', 'defrost']],
  ['regression: scenario 2',
   [4,
    4,
    [[True, 40, 50],
     [True, 40, 35],
     [True, 40, 60],
     [False, 56, 60],
     [True, 56, 35],
     [True, 50, 50],
     [True, 32, 35],
     [True, 32, 51],
     [True, 32, 20],
     [True, 32, 51],
     [True, 32, 60],
     [True, 57, 35],
     [True, 32, 50],
     [True, 32, 35],
     [True, 20, 35],
     [True, 50, 35],
     [True, 57, 35],
     [True, 57, 51],
     [False, 57, 50]]],
   ['heat',
    'heat',
    'heat',
    'off',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'heat',
    'heat',
    'off']],
  ['regression: scenario 3',
   [3,
    6,
    [[False, 56, 51],
     [True, 56, 35],
     [False, 56, 35],
     [True, 56, 35],
     [True, 56, 35],
     [True, 33, 50],
     [True, 33, 20],
     [True, 33, 50],
     [False, 33, 60],
     [True, 33, 35],
     [True, 33, 35],
     [True, 33, 50],
     [True, 33, 60],
     [True, 33, 35],
     [True, 33, 35],
     [True, 20, 50],
     [True, 20, 51]]],
   ['off',
    'heat',
    'off',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'off',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat']],
  ['regression: scenario 4',
   [4,
    4,
    [[False, 40, 50],
     [True, 40, 50],
     [True, 40, 35],
     [True, 40, 50],
     [True, 40, 50],
     [True, 28, 50],
     [True, 28, 50],
     [False, 28, 60],
     [False, 28, 20],
     [True, 28, 60],
     [True, 28, 50],
     [False, 28, 60],
     [True, 28, 50],
     [True, 28, 35],
     [False, 28, 50],
     [True, 28, 20],
     [True, 28, 51],
     [True, 33, 20]]],
   ['off',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'off',
    'off',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'off',
    'heat',
    'heat',
    'heat']]],
 [['regression: scenario 2',
   [4,
    3,
    [[True, 32, 20],
     [True, 57, 60],
     [True, 57, 60],
     [True, 57, 20],
     [False, 40, 51],
     [True, 50, 50],
     [True, 50, 51],
     [True, 50, 50],
     [True, 56, 60],
     [True, 40, 20],
     [False, 40, 35],
     [True, 50, 35],
     [False, 50, 51],
     [False, 50, 35],
     [True, 57, 35],
     [True, 57, 20],
     [True, 57, 20],
     [True, 57, 50],
     [True, 57, 60]]],
   ['heat',
    'heat',
    'heat',
    'heat',
    'off',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'off',
    'heat',
    'off',
    'off',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat']],
  ['regression: scenario 3',
   [3,
    6,
    [[True, 20, 60],
     [True, 33, 20],
     [True, 33, 60],
     [True, 33, 51],
     [True, 33, 35],
     [True, 32, 50],
     [True, 32, 35],
     [True, 32, 35],
     [True, 32, 60],
     [True, 32, 60],
     [False, 32, 60],
     [True, 32, 35],
     [False, 32, 50],
     [True, 40, 50]]],
   ['heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'off',
    'heat']],
  ['regression: two defrosts',
   [3,
    4,
    [[True, 30, 20],
     [True, 30, 20],
     [False, 30, 20],
     [True, 32, 20],
     [True, 40, 20],
     [True, 45, 20],
     [True, 57, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20]]],
   ['heat',
    'heat',
    'off',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'heat',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'heat']],
  ['control: warm outdoor inhibits',
   [2, 3, [[True, 30, 55], [True, 30, 55], [True, 30, 50], [True, 60, 50], [True, 30, 50]]],
   ['heat', 'heat', 'defrost', 'heat', 'heat']],
  ['regression: dry coil runtime',
   [2, 3, [[True, 40, 20], [True, 33, 20], [True, 32, 20], [True, 31, 20], [True, 50, 20]]],
   ['heat', 'heat', 'heat', 'defrost', 'defrost']],
  ['control: exact termination temperature',
   [1, 5, [[True, 30, 20], [True, 56, 20], [True, 57, 20], [False, 30, 20], [True, 30, 20]]],
   ['defrost', 'defrost', 'heat', 'off', 'defrost']],
  ['regression: scenario 1',
   [4,
    6,
    [[True, 33, 20],
     [True, 28, 50],
     [True, 56, 51],
     [True, 33, 51],
     [True, 28, 35],
     [False, 28, 50],
     [True, 28, 60],
     [True, 28, 20],
     [True, 40, 50],
     [True, 40, 35],
     [True, 40, 51],
     [True, 40, 50],
     [True, 28, 60],
     [True, 28, 50],
     [True, 50, 35],
     [True, 60, 50],
     [True, 57, 20],
     [True, 40, 50]]],
   ['heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'off',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat']],
  ['regression: scenario 4',
   [3,
    3,
    [[True, 28, 51],
     [True, 28, 35],
     [True, 56, 50],
     [False, 56, 51],
     [True, 56, 50],
     [True, 56, 20],
     [False, 40, 50],
     [True, 40, 20],
     [False, 60, 20],
     [True, 50, 50],
     [True, 56, 35],
     [True, 56, 35],
     [True, 56, 51],
     [True, 32, 60],
     [True, 32, 60],
     [True, 32, 35],
     [True, 32, 60],
     [True, 32, 20],
     [True, 32, 50],
     [True, 32, 60],
     [True, 32, 51],
     [True, 40, 20],
     [True, 40, 20],
     [True, 40, 20]]],
   ['heat',
    'heat',
    'heat',
    'off',
    'heat',
    'heat',
    'off',
    'heat',
    'off',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat']]],
 [['regression: scenario 4',
   [4,
    6,
    [[True, 28, 50],
     [True, 28, 35],
     [True, 28, 50],
     [True, 50, 35],
     [True, 40, 50],
     [True, 40, 51],
     [False, 40, 35],
     [True, 20, 50],
     [True, 20, 35],
     [True, 28, 50],
     [True, 32, 51],
     [True, 32, 51],
     [True, 28, 51],
     [False, 28, 50]]],
   ['heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'off',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'off']],
  ['regression: scenario 13',
   [4,
    4,
    [[True, 20, 51],
     [True, 20, 50],
     [True, 32, 20],
     [True, 56, 35],
     [True, 56, 50],
     [True, 56, 51],
     [True, 56, 50],
     [True, 56, 20],
     [True, 32, 20],
     [True, 32, 51],
     [True, 32, 60],
     [True, 33, 51],
     [True, 28, 60],
     [True, 28, 50],
     [True, 28, 50],
     [True, 28, 51],
     [True, 28, 50],
     [True, 28, 51]]],
   ['heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'heat',
    'heat',
    'heat',
    'defrost',
    'defrost']],
  ['regression: two defrosts',
   [3,
    4,
    [[True, 30, 20],
     [True, 30, 20],
     [False, 30, 20],
     [True, 32, 20],
     [True, 40, 20],
     [True, 45, 20],
     [True, 57, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20]]],
   ['heat',
    'heat',
    'off',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'heat',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'heat']],
  ['control: warm outdoor inhibits',
   [2, 3, [[True, 30, 55], [True, 30, 55], [True, 30, 50], [True, 60, 50], [True, 30, 50]]],
   ['heat', 'heat', 'defrost', 'heat', 'heat']],
  ['regression: dry coil runtime',
   [2, 3, [[True, 40, 20], [True, 33, 20], [True, 32, 20], [True, 31, 20], [True, 50, 20]]],
   ['heat', 'heat', 'heat', 'defrost', 'defrost']],
  ['control: exact termination temperature',
   [1, 5, [[True, 30, 20], [True, 56, 20], [True, 57, 20], [False, 30, 20], [True, 30, 20]]],
   ['defrost', 'defrost', 'heat', 'off', 'defrost']],
  ['regression: scenario 1',
   [5,
    4,
    [[True, 57, 60],
     [True, 57, 50],
     [True, 57, 50],
     [True, 57, 35],
     [True, 33, 50],
     [True, 33, 50],
     [True, 32, 50],
     [True, 50, 51],
     [True, 50, 51],
     [False, 50, 20],
     [False, 33, 50],
     [True, 56, 20],
     [True, 32, 60],
     [True, 32, 35],
     [True, 32, 20]]],
   ['heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'off',
    'off',
    'heat',
    'heat',
    'heat',
    'heat']],
  ['regression: scenario 2',
   [4,
    6,
    [[False, 28, 50],
     [True, 28, 51],
     [True, 28, 35],
     [True, 28, 50],
     [True, 57, 50],
     [True, 57, 20],
     [True, 57, 50],
     [True, 57, 50],
     [True, 56, 50],
     [True, 56, 35],
     [True, 56, 51],
     [True, 56, 50]]],
   ['off', 'heat', 'heat', 'heat', 'heat', 'heat', 'heat', 'heat', 'heat', 'heat', 'heat', 'heat']]],
 [['regression: scenario 4',
   [5,
    4,
    [[True, 28, 50],
     [True, 28, 35],
     [True, 28, 50],
     [True, 57, 51],
     [True, 57, 50],
     [True, 57, 20],
     [True, 57, 35],
     [True, 57, 20],
     [True, 57, 35],
     [True, 56, 20],
     [False, 56, 20],
     [True, 33, 35],
     [True, 33, 60],
     [True, 33, 50],
     [True, 20, 50]]],
   ['heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'off',
    'heat',
    'heat',
    'heat',
    'heat']],
  ['regression: scenario 6',
   [4,
    4,
    [[True, 40, 51],
     [True, 40, 20],
     [False, 40, 35],
     [True, 28, 51],
     [True, 28, 20],
     [True, 28, 60],
     [False, 28, 51],
     [False, 28, 51],
     [False, 32, 60],
     [True, 32, 35],
     [True, 20, 51],
     [True, 20, 35],
     [True, 20, 50],
     [True, 20, 20],
     [False, 20, 35]]],
   ['heat',
    'heat',
    'off',
    'heat',
    'heat',
    'heat',
    'off',
    'off',
    'off',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'off']],
  ['regression: two defrosts',
   [3,
    4,
    [[True, 30, 20],
     [True, 30, 20],
     [False, 30, 20],
     [True, 32, 20],
     [True, 40, 20],
     [True, 45, 20],
     [True, 57, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20]]],
   ['heat',
    'heat',
    'off',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'heat',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'heat']],
  ['control: warm outdoor inhibits',
   [2, 3, [[True, 30, 55], [True, 30, 55], [True, 30, 50], [True, 60, 50], [True, 30, 50]]],
   ['heat', 'heat', 'defrost', 'heat', 'heat']],
  ['regression: dry coil runtime',
   [2, 3, [[True, 40, 20], [True, 33, 20], [True, 32, 20], [True, 31, 20], [True, 50, 20]]],
   ['heat', 'heat', 'heat', 'defrost', 'defrost']],
  ['control: exact termination temperature',
   [1, 5, [[True, 30, 20], [True, 56, 20], [True, 57, 20], [False, 30, 20], [True, 30, 20]]],
   ['defrost', 'defrost', 'heat', 'off', 'defrost']],
  ['regression: scenario 1',
   [4,
    6,
    [[True, 32, 50],
     [True, 50, 50],
     [True, 50, 35],
     [True, 57, 51],
     [True, 57, 20],
     [False, 57, 51],
     [True, 57, 50],
     [True, 57, 51],
     [True, 32, 50],
     [True, 32, 51],
     [True, 32, 50],
     [False, 28, 50]]],
   ['heat', 'heat', 'heat', 'heat', 'heat', 'off', 'heat', 'heat', 'heat', 'heat', 'defrost', 'defrost']],
  ['regression: scenario 2',
   [3,
    4,
    [[True, 32, 35],
     [True, 32, 35],
     [True, 33, 60],
     [True, 33, 50],
     [True, 33, 60],
     [True, 57, 51],
     [True, 20, 60],
     [True, 20, 50],
     [True, 33, 50],
     [False, 33, 51],
     [False, 33, 20],
     [True, 33, 20],
     [True, 40, 50],
     [True, 40, 50],
     [True, 40, 35],
     [True, 40, 35],
     [True, 40, 51],
     [True, 28, 35],
     [True, 28, 51],
     [True, 33, 60],
     [False, 33, 60],
     [True, 56, 51],
     [True, 56, 60],
     [False, 56, 60]]],
   ['heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'off',
    'heat',
    'heat',
    'off']]]]
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
regression: dry coil runtime['heat', 'heat', 'heat', 'heat', 'heat']['heat', 'heat', 'heat', 'defrost', 'defrost']Failed
regression: two defrosts['heat', 'heat', 'off', 'heat', 'heat', 'heat', 'heat', 'defrost', 'defrost', 'defrost', 'defrost', 'heat', 'heat', 'heat']['heat', 'heat', 'off', 'defrost', 'defrost', 'defrost', 'heat', 'heat', 'heat', 'defrost', 'defrost', 'defrost', 'defrost', 'heat']Failed
control: warm outdoor inhibits['heat', 'heat', 'defrost', 'heat', 'heat']['heat', 'heat', 'defrost', 'heat', 'heat']Passed
control: exact termination temperature['defrost', 'defrost', 'heat', 'off', 'defrost']['defrost', 'defrost', 'heat', 'off', 'defrost']Passed
regression: scenario 1['heat', 'heat', 'heat', 'heat', 'heat', 'heat', 'off', 'off', 'heat', 'heat', 'heat', 'heat', 'heat', 'heat', 'off', 'heat', 'off', 'off', 'heat', 'off']['heat', 'heat', 'heat', 'heat', 'heat', 'heat', 'off', 'off', 'heat', 'heat', 'heat', 'heat', 'heat', 'heat', 'off', 'heat', 'off', 'off', 'heat', 'off']Passed
regression: scenario 2['heat', 'off', 'heat', 'heat', 'heat', 'heat', 'heat', 'heat', 'heat', 'off', 'heat', 'defrost', 'defrost', 'defrost', 'heat', 'heat', 'off']['heat', 'off', 'heat', 'heat', 'heat', 'heat', 'heat', 'heat', 'heat', 'off', 'heat', 'defrost', 'defrost', 'defrost', 'heat', 'heat', 'off']Passed
control: scenario 3['heat', 'heat', 'heat', 'heat', 'defrost', 'defrost', 'defrost', 'heat', 'heat', 'heat', 'off', 'heat']['heat', 'heat', 'heat', 'heat', 'defrost', 'defrost', 'defrost', 'heat', 'heat', 'heat', 'off', 'heat']Passed
regression: scenario 4['heat', 'heat', 'heat', 'defrost', 'defrost', 'defrost', 'defrost', 'heat', 'off', 'heat', 'heat', 'off', 'heat', 'off', 'heat', 'heat', 'heat', 'heat', 'defrost', 'defrost']['heat', 'heat', 'heat', 'defrost', 'defrost', 'defrost', 'defrost', 'heat', 'off', 'heat', 'heat', 'off', 'heat', 'off', 'heat', 'heat', 'heat', 'heat', 'defrost', 'defrost']Passed

SHA-256 / 293fed9d02957e516ec1c20a242f299b597043f3f7c030991ae6a4f8966f9faf

3 / The verified repair

Exit 0
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(interval, max_minutes, samples):
    acc = 0
    defrost_min = None
    out = []
    for running, coil, outdoor in samples:
        if defrost_min is not None:
            defrost_min += 1
            if coil >= 57 or defrost_min >= max_minutes:
                defrost_min = None
                out.append('heat' if running else 'off')
            else:
                out.append('defrost')
            continue
        if running and coil <= 32:
            acc += 1
        if acc >= interval and outdoor <= 50:
            acc = 0
            defrost_min = 0
            out.append('defrost')
            continue
        out.append('heat' if running else 'off')
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['regression: dry coil runtime',
   [2, 3, [[True, 40, 20], [True, 33, 20], [True, 32, 20], [True, 31, 20], [True, 50, 20]]],
   ['heat', 'heat', 'heat', 'defrost', 'defrost']],
  ['regression: two defrosts',
   [3,
    4,
    [[True, 30, 20],
     [True, 30, 20],
     [False, 30, 20],
     [True, 32, 20],
     [True, 40, 20],
     [True, 45, 20],
     [True, 57, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20]]],
   ['heat',
    'heat',
    'off',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'heat',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'heat']],
  ['control: warm outdoor inhibits',
   [2, 3, [[True, 30, 55], [True, 30, 55], [True, 30, 50], [True, 60, 50], [True, 30, 50]]],
   ['heat', 'heat', 'defrost', 'heat', 'heat']],
  ['control: exact termination temperature',
   [1, 5, [[True, 30, 20], [True, 56, 20], [True, 57, 20], [False, 30, 20], [True, 30, 20]]],
   ['defrost', 'defrost', 'heat', 'off', 'defrost']],
  ['regression: scenario 1',
   [3,
    3,
    [[True, 40, 35],
     [True, 40, 50],
     [True, 40, 51],
     [True, 40, 51],
     [True, 40, 50],
     [True, 40, 50],
     [False, 20, 35],
     [False, 20, 51],
     [True, 20, 50],
     [True, 50, 20],
     [True, 50, 50],
     [True, 56, 50],
     [True, 40, 50],
     [True, 40, 50],
     [False, 40, 51],
     [True, 40, 50],
     [False, 20, 51],
     [False, 20, 60],
     [True, 57, 51],
     [False, 57, 51]]],
   ['heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'off',
    'off',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'off',
    'heat',
    'off',
    'off',
    'heat',
    'off']],
  ['regression: scenario 2',
   [4,
    3,
    [[True, 33, 60],
     [False, 57, 20],
     [True, 57, 50],
     [True, 60, 20],
     [True, 60, 35],
     [True, 60, 50],
     [True, 28, 50],
     [True, 28, 20],
     [True, 28, 20],
     [False, 28, 50],
     [True, 28, 51],
     [True, 28, 35],
     [True, 28, 60],
     [True, 28, 50],
     [True, 40, 50],
     [True, 40, 50],
     [False, 40, 60]]],
   ['heat',
    'off',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'off',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'heat',
    'off']],
  ['control: scenario 3',
   [5,
    3,
    [[True, 20, 20],
     [True, 20, 50],
     [True, 20, 50],
     [True, 20, 50],
     [True, 20, 35],
     [True, 40, 50],
     [False, 40, 20],
     [True, 40, 50],
     [True, 40, 50],
     [True, 33, 60],
     [False, 33, 60],
     [True, 60, 50]]],
   ['heat', 'heat', 'heat', 'heat', 'defrost', 'defrost', 'defrost', 'heat', 'heat', 'heat', 'off', 'heat']],
  ['regression: scenario 4',
   [3,
    4,
    [[True, 20, 50],
     [True, 20, 35],
     [True, 20, 60],
     [True, 20, 50],
     [False, 20, 50],
     [True, 20, 35],
     [True, 20, 60],
     [True, 20, 51],
     [False, 20, 20],
     [True, 50, 50],
     [True, 50, 50],
     [False, 50, 50],
     [True, 50, 35],
     [False, 33, 60],
     [True, 33, 60],
     [True, 33, 50],
     [True, 20, 35],
     [True, 20, 35],
     [True, 20, 50],
     [True, 50, 20]]],
   ['heat',
    'heat',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'off',
    'heat',
    'heat',
    'off',
    'heat',
    'off',
    'heat',
    'heat',
    'heat',
    'heat',
    'defrost',
    'defrost']]],
 [['regression: scenario 1',
   [3,
    3,
    [[True, 28, 20],
     [True, 28, 50],
     [True, 32, 50],
     [False, 32, 35],
     [True, 60, 20],
     [True, 60, 35],
     [True, 60, 50],
     [True, 60, 50],
     [True, 57, 50],
     [True, 57, 50],
     [True, 60, 60],
     [False, 60, 50],
     [True, 60, 35],
     [True, 33, 50]]],
   ['heat',
    'heat',
    'defrost',
    'defrost',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'off',
    'heat',
    'heat']],
  ['regression: dry coil runtime',
   [2, 3, [[True, 40, 20], [True, 33, 20], [True, 32, 20], [True, 31, 20], [True, 50, 20]]],
   ['heat', 'heat', 'heat', 'defrost', 'defrost']],
  ['regression: two defrosts',
   [3,
    4,
    [[True, 30, 20],
     [True, 30, 20],
     [False, 30, 20],
     [True, 32, 20],
     [True, 40, 20],
     [True, 45, 20],
     [True, 57, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20]]],
   ['heat',
    'heat',
    'off',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'heat',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'heat']],
  ['control: warm outdoor inhibits',
   [2, 3, [[True, 30, 55], [True, 30, 55], [True, 30, 50], [True, 60, 50], [True, 30, 50]]],
   ['heat', 'heat', 'defrost', 'heat', 'heat']],
  ['control: exact termination temperature',
   [1, 5, [[True, 30, 20], [True, 56, 20], [True, 57, 20], [False, 30, 20], [True, 30, 20]]],
   ['defrost', 'defrost', 'heat', 'off', 'defrost']],
  ['regression: scenario 2',
   [4,
    4,
    [[True, 40, 50],
     [True, 40, 35],
     [True, 40, 60],
     [False, 56, 60],
     [True, 56, 35],
     [True, 50, 50],
     [True, 32, 35],
     [True, 32, 51],
     [True, 32, 20],
     [True, 32, 51],
     [True, 32, 60],
     [True, 57, 35],
     [True, 32, 50],
     [True, 32, 35],
     [True, 20, 35],
     [True, 50, 35],
     [True, 57, 35],
     [True, 57, 51],
     [False, 57, 50]]],
   ['heat',
    'heat',
    'heat',
    'off',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'heat',
    'heat',
    'off']],
  ['regression: scenario 3',
   [3,
    6,
    [[False, 56, 51],
     [True, 56, 35],
     [False, 56, 35],
     [True, 56, 35],
     [True, 56, 35],
     [True, 33, 50],
     [True, 33, 20],
     [True, 33, 50],
     [False, 33, 60],
     [True, 33, 35],
     [True, 33, 35],
     [True, 33, 50],
     [True, 33, 60],
     [True, 33, 35],
     [True, 33, 35],
     [True, 20, 50],
     [True, 20, 51]]],
   ['off',
    'heat',
    'off',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'off',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat']],
  ['regression: scenario 4',
   [4,
    4,
    [[False, 40, 50],
     [True, 40, 50],
     [True, 40, 35],
     [True, 40, 50],
     [True, 40, 50],
     [True, 28, 50],
     [True, 28, 50],
     [False, 28, 60],
     [False, 28, 20],
     [True, 28, 60],
     [True, 28, 50],
     [False, 28, 60],
     [True, 28, 50],
     [True, 28, 35],
     [False, 28, 50],
     [True, 28, 20],
     [True, 28, 51],
     [True, 33, 20]]],
   ['off',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'off',
    'off',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'off',
    'heat',
    'heat',
    'heat']]],
 [['regression: scenario 2',
   [4,
    3,
    [[True, 32, 20],
     [True, 57, 60],
     [True, 57, 60],
     [True, 57, 20],
     [False, 40, 51],
     [True, 50, 50],
     [True, 50, 51],
     [True, 50, 50],
     [True, 56, 60],
     [True, 40, 20],
     [False, 40, 35],
     [True, 50, 35],
     [False, 50, 51],
     [False, 50, 35],
     [True, 57, 35],
     [True, 57, 20],
     [True, 57, 20],
     [True, 57, 50],
     [True, 57, 60]]],
   ['heat',
    'heat',
    'heat',
    'heat',
    'off',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'off',
    'heat',
    'off',
    'off',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat']],
  ['regression: scenario 3',
   [3,
    6,
    [[True, 20, 60],
     [True, 33, 20],
     [True, 33, 60],
     [True, 33, 51],
     [True, 33, 35],
     [True, 32, 50],
     [True, 32, 35],
     [True, 32, 35],
     [True, 32, 60],
     [True, 32, 60],
     [False, 32, 60],
     [True, 32, 35],
     [False, 32, 50],
     [True, 40, 50]]],
   ['heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'off',
    'heat']],
  ['regression: two defrosts',
   [3,
    4,
    [[True, 30, 20],
     [True, 30, 20],
     [False, 30, 20],
     [True, 32, 20],
     [True, 40, 20],
     [True, 45, 20],
     [True, 57, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20]]],
   ['heat',
    'heat',
    'off',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'heat',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'heat']],
  ['control: warm outdoor inhibits',
   [2, 3, [[True, 30, 55], [True, 30, 55], [True, 30, 50], [True, 60, 50], [True, 30, 50]]],
   ['heat', 'heat', 'defrost', 'heat', 'heat']],
  ['regression: dry coil runtime',
   [2, 3, [[True, 40, 20], [True, 33, 20], [True, 32, 20], [True, 31, 20], [True, 50, 20]]],
   ['heat', 'heat', 'heat', 'defrost', 'defrost']],
  ['control: exact termination temperature',
   [1, 5, [[True, 30, 20], [True, 56, 20], [True, 57, 20], [False, 30, 20], [True, 30, 20]]],
   ['defrost', 'defrost', 'heat', 'off', 'defrost']],
  ['regression: scenario 1',
   [4,
    6,
    [[True, 33, 20],
     [True, 28, 50],
     [True, 56, 51],
     [True, 33, 51],
     [True, 28, 35],
     [False, 28, 50],
     [True, 28, 60],
     [True, 28, 20],
     [True, 40, 50],
     [True, 40, 35],
     [True, 40, 51],
     [True, 40, 50],
     [True, 28, 60],
     [True, 28, 50],
     [True, 50, 35],
     [True, 60, 50],
     [True, 57, 20],
     [True, 40, 50]]],
   ['heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'off',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat']],
  ['regression: scenario 4',
   [3,
    3,
    [[True, 28, 51],
     [True, 28, 35],
     [True, 56, 50],
     [False, 56, 51],
     [True, 56, 50],
     [True, 56, 20],
     [False, 40, 50],
     [True, 40, 20],
     [False, 60, 20],
     [True, 50, 50],
     [True, 56, 35],
     [True, 56, 35],
     [True, 56, 51],
     [True, 32, 60],
     [True, 32, 60],
     [True, 32, 35],
     [True, 32, 60],
     [True, 32, 20],
     [True, 32, 50],
     [True, 32, 60],
     [True, 32, 51],
     [True, 40, 20],
     [True, 40, 20],
     [True, 40, 20]]],
   ['heat',
    'heat',
    'heat',
    'off',
    'heat',
    'heat',
    'off',
    'heat',
    'off',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat']]],
 [['regression: scenario 4',
   [4,
    6,
    [[True, 28, 50],
     [True, 28, 35],
     [True, 28, 50],
     [True, 50, 35],
     [True, 40, 50],
     [True, 40, 51],
     [False, 40, 35],
     [True, 20, 50],
     [True, 20, 35],
     [True, 28, 50],
     [True, 32, 51],
     [True, 32, 51],
     [True, 28, 51],
     [False, 28, 50]]],
   ['heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'off',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'off']],
  ['regression: scenario 13',
   [4,
    4,
    [[True, 20, 51],
     [True, 20, 50],
     [True, 32, 20],
     [True, 56, 35],
     [True, 56, 50],
     [True, 56, 51],
     [True, 56, 50],
     [True, 56, 20],
     [True, 32, 20],
     [True, 32, 51],
     [True, 32, 60],
     [True, 33, 51],
     [True, 28, 60],
     [True, 28, 50],
     [True, 28, 50],
     [True, 28, 51],
     [True, 28, 50],
     [True, 28, 51]]],
   ['heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'heat',
    'heat',
    'heat',
    'defrost',
    'defrost']],
  ['regression: two defrosts',
   [3,
    4,
    [[True, 30, 20],
     [True, 30, 20],
     [False, 30, 20],
     [True, 32, 20],
     [True, 40, 20],
     [True, 45, 20],
     [True, 57, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20]]],
   ['heat',
    'heat',
    'off',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'heat',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'heat']],
  ['control: warm outdoor inhibits',
   [2, 3, [[True, 30, 55], [True, 30, 55], [True, 30, 50], [True, 60, 50], [True, 30, 50]]],
   ['heat', 'heat', 'defrost', 'heat', 'heat']],
  ['regression: dry coil runtime',
   [2, 3, [[True, 40, 20], [True, 33, 20], [True, 32, 20], [True, 31, 20], [True, 50, 20]]],
   ['heat', 'heat', 'heat', 'defrost', 'defrost']],
  ['control: exact termination temperature',
   [1, 5, [[True, 30, 20], [True, 56, 20], [True, 57, 20], [False, 30, 20], [True, 30, 20]]],
   ['defrost', 'defrost', 'heat', 'off', 'defrost']],
  ['regression: scenario 1',
   [5,
    4,
    [[True, 57, 60],
     [True, 57, 50],
     [True, 57, 50],
     [True, 57, 35],
     [True, 33, 50],
     [True, 33, 50],
     [True, 32, 50],
     [True, 50, 51],
     [True, 50, 51],
     [False, 50, 20],
     [False, 33, 50],
     [True, 56, 20],
     [True, 32, 60],
     [True, 32, 35],
     [True, 32, 20]]],
   ['heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'off',
    'off',
    'heat',
    'heat',
    'heat',
    'heat']],
  ['regression: scenario 2',
   [4,
    6,
    [[False, 28, 50],
     [True, 28, 51],
     [True, 28, 35],
     [True, 28, 50],
     [True, 57, 50],
     [True, 57, 20],
     [True, 57, 50],
     [True, 57, 50],
     [True, 56, 50],
     [True, 56, 35],
     [True, 56, 51],
     [True, 56, 50]]],
   ['off', 'heat', 'heat', 'heat', 'heat', 'heat', 'heat', 'heat', 'heat', 'heat', 'heat', 'heat']]],
 [['regression: scenario 4',
   [5,
    4,
    [[True, 28, 50],
     [True, 28, 35],
     [True, 28, 50],
     [True, 57, 51],
     [True, 57, 50],
     [True, 57, 20],
     [True, 57, 35],
     [True, 57, 20],
     [True, 57, 35],
     [True, 56, 20],
     [False, 56, 20],
     [True, 33, 35],
     [True, 33, 60],
     [True, 33, 50],
     [True, 20, 50]]],
   ['heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'off',
    'heat',
    'heat',
    'heat',
    'heat']],
  ['regression: scenario 6',
   [4,
    4,
    [[True, 40, 51],
     [True, 40, 20],
     [False, 40, 35],
     [True, 28, 51],
     [True, 28, 20],
     [True, 28, 60],
     [False, 28, 51],
     [False, 28, 51],
     [False, 32, 60],
     [True, 32, 35],
     [True, 20, 51],
     [True, 20, 35],
     [True, 20, 50],
     [True, 20, 20],
     [False, 20, 35]]],
   ['heat',
    'heat',
    'off',
    'heat',
    'heat',
    'heat',
    'off',
    'off',
    'off',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'off']],
  ['regression: two defrosts',
   [3,
    4,
    [[True, 30, 20],
     [True, 30, 20],
     [False, 30, 20],
     [True, 32, 20],
     [True, 40, 20],
     [True, 45, 20],
     [True, 57, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20],
     [True, 20, 20]]],
   ['heat',
    'heat',
    'off',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'heat',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'heat']],
  ['control: warm outdoor inhibits',
   [2, 3, [[True, 30, 55], [True, 30, 55], [True, 30, 50], [True, 60, 50], [True, 30, 50]]],
   ['heat', 'heat', 'defrost', 'heat', 'heat']],
  ['regression: dry coil runtime',
   [2, 3, [[True, 40, 20], [True, 33, 20], [True, 32, 20], [True, 31, 20], [True, 50, 20]]],
   ['heat', 'heat', 'heat', 'defrost', 'defrost']],
  ['control: exact termination temperature',
   [1, 5, [[True, 30, 20], [True, 56, 20], [True, 57, 20], [False, 30, 20], [True, 30, 20]]],
   ['defrost', 'defrost', 'heat', 'off', 'defrost']],
  ['regression: scenario 1',
   [4,
    6,
    [[True, 32, 50],
     [True, 50, 50],
     [True, 50, 35],
     [True, 57, 51],
     [True, 57, 20],
     [False, 57, 51],
     [True, 57, 50],
     [True, 57, 51],
     [True, 32, 50],
     [True, 32, 51],
     [True, 32, 50],
     [False, 28, 50]]],
   ['heat', 'heat', 'heat', 'heat', 'heat', 'off', 'heat', 'heat', 'heat', 'heat', 'defrost', 'defrost']],
  ['regression: scenario 2',
   [3,
    4,
    [[True, 32, 35],
     [True, 32, 35],
     [True, 33, 60],
     [True, 33, 50],
     [True, 33, 60],
     [True, 57, 51],
     [True, 20, 60],
     [True, 20, 50],
     [True, 33, 50],
     [False, 33, 51],
     [False, 33, 20],
     [True, 33, 20],
     [True, 40, 50],
     [True, 40, 50],
     [True, 40, 35],
     [True, 40, 35],
     [True, 40, 51],
     [True, 28, 35],
     [True, 28, 51],
     [True, 33, 60],
     [False, 33, 60],
     [True, 56, 51],
     [True, 56, 60],
     [False, 56, 60]]],
   ['heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'defrost',
    'defrost',
    'defrost',
    'defrost',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'heat',
    'off',
    'heat',
    'heat',
    'off']]]]
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
regression: dry coil runtime['heat', 'heat', 'heat', 'defrost', 'defrost']['heat', 'heat', 'heat', 'defrost', 'defrost']Passed
regression: two defrosts['heat', 'heat', 'off', 'defrost', 'defrost', 'defrost', 'heat', 'heat', 'heat', 'defrost', 'defrost', 'defrost', 'defrost', 'heat']['heat', 'heat', 'off', 'defrost', 'defrost', 'defrost', 'heat', 'heat', 'heat', 'defrost', 'defrost', 'defrost', 'defrost', 'heat']Passed
control: warm outdoor inhibits['heat', 'heat', 'defrost', 'heat', 'heat']['heat', 'heat', 'defrost', 'heat', 'heat']Passed
control: exact termination temperature['defrost', 'defrost', 'heat', 'off', 'defrost']['defrost', 'defrost', 'heat', 'off', 'defrost']Passed
regression: scenario 1['heat', 'heat', 'heat', 'heat', 'heat', 'heat', 'off', 'off', 'heat', 'heat', 'heat', 'heat', 'heat', 'heat', 'off', 'heat', 'off', 'off', 'heat', 'off']['heat', 'heat', 'heat', 'heat', 'heat', 'heat', 'off', 'off', 'heat', 'heat', 'heat', 'heat', 'heat', 'heat', 'off', 'heat', 'off', 'off', 'heat', 'off']Passed
regression: scenario 2['heat', 'off', 'heat', 'heat', 'heat', 'heat', 'heat', 'heat', 'heat', 'off', 'heat', 'defrost', 'defrost', 'defrost', 'heat', 'heat', 'off']['heat', 'off', 'heat', 'heat', 'heat', 'heat', 'heat', 'heat', 'heat', 'off', 'heat', 'defrost', 'defrost', 'defrost', 'heat', 'heat', 'off']Passed
control: scenario 3['heat', 'heat', 'heat', 'heat', 'defrost', 'defrost', 'defrost', 'heat', 'heat', 'heat', 'off', 'heat']['heat', 'heat', 'heat', 'heat', 'defrost', 'defrost', 'defrost', 'heat', 'heat', 'heat', 'off', 'heat']Passed
regression: scenario 4['heat', 'heat', 'heat', 'defrost', 'defrost', 'defrost', 'defrost', 'heat', 'off', 'heat', 'heat', 'off', 'heat', 'off', 'heat', 'heat', 'heat', 'heat', 'defrost', 'defrost']['heat', 'heat', 'heat', 'defrost', 'defrost', 'defrost', 'defrost', 'heat', 'off', 'heat', 'heat', 'off', 'heat', 'off', 'heat', 'heat', 'heat', 'heat', 'defrost', 'defrost']Passed

SHA-256 / 67cdfeaf2269b3e0f381eeeaafc93ba77553e43e708d7479d7e22710177bce92

Verification & scope

A deterministic bounded teaching model of one thermostat or HVAC controller decision evaluated per sample. Temperatures are integer tenths of a degree Fahrenheit unless stated otherwise. The contract is a stipulated toy convention, not a claim of conformance to any manufacturer, ASHRAE guideline or code. 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 2026-09-29T14:51:45.709831+00:00.

Case digest / 67877b6bc93e07b0d417ab9dc9078cd4b0222a3a552e2aaf355c0a1892dc16db