FAILURE MAP
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FA-93186 / EV charging session scheduling / Open access

Demand-response curtailment of a charge plan: curtailed energy sign · case 01

Curtailment reports a negative reduction.

Verified by executionVariant 1 · 7 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The difference is computed as new minus plan.

THE FAILURE

The difference is computed as new minus plan.

Unsuccessful approach: Counting curtailed slots reports slots instead of watts.

Case contract

profile is planned watts per slot. events are [start, end, pct, opt_out]; during [start, end) a non-opted-out event limits power to pct percent of plan (integer floor of p*pct/100), and overlapping events apply the lowest pct. Curtailed power never drops below min(plan, floor_w). Return [new profile, total curtailed watts over slots].

Why this case matters

Depot, workplace and public EV chargers schedule sessions against prices, circuit limits and departure deadlines; a wrong decision silently strands a driver or overloads a feeder.

1 / The failure

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

N = 1
observations = []
def solve(profile, events, floor_w):
    out = []
    for t, p in enumerate(profile):
        pct = 100
        for s, e, q, opt in events:
            if opt:
                continue
            if s <= t < e and q < pct:
                pct = q
        new = p * pct // 100
        new = max(new, min(p, floor_w))
        out.append(new)
    return [out, sum(out) - sum(profile)]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['boundary: event ends at slot', [[3680, 3680, 3680], [[0, 1, 50, False]], 0],
   [[1840, 3680, 3680], 1840]],
  ['boundary: opted-out event', [[7400, 7400], [[0, 2, 0, True]], 1380], [[7400, 7400], 0]],
  ['boundary: plan below floor', [[1000, 7400], [[0, 2, 0, False]], 1380], [[1000, 1380], 6020]],
  ['regression: curtailed energy sign',
   [[11000, 1000, 7400, 1380, 2345, 1380, 7400, 7400, 1111],
    [[8, 13, 50, False], [5, 8, 60, False]], 2000],
   [[11000, 1000, 7400, 1380, 2345, 1380, 4440, 4440, 1111], 5920]],
  ['regression: curtailed energy sign (partial repair)',
   [[1380, 1000, 3333, 2345, 1000, 1380, 11000, 3333, 3680, 0],
    [[8, 9, 60, False], [9, 10, 25, True], [4, 9, 75, True]], 0],
   [[1380, 1000, 3333, 2345, 1000, 1380, 11000, 3333, 2208, 0], 1472]],
  ['control 1',
   [[1000, 3333, 1111, 1380, 11000], [[1, 2, 75, True], [5, 8, 75, False], [4, 5, 25, False]], 0],
   [[1000, 3333, 1111, 1380, 2750], 8250]],
  ['control 2',
   [[1380, 1000, 1111, 1000, 1000, 3333, 3333, 7400, 1111, 3680, 11000, 1111],
    [[8, 12, 60, False], [5, 7, 0, False]], 2000],
   [[1380, 1000, 1111, 1000, 1000, 2000, 2000, 7400, 1111, 2208, 6600, 1111], 8538]]],
 [['boundary: event ends at slot', [[3680, 3680, 3680], [[0, 1, 50, False]], 0],
   [[1840, 3680, 3680], 1840]],
  ['boundary: opted-out event', [[7400, 7400], [[0, 2, 0, True]], 1380], [[7400, 7400], 0]],
  ['boundary: plan below floor', [[1000, 7400], [[0, 2, 0, False]], 1380], [[1000, 1380], 6020]],
  ['regression: curtailed energy sign', [[3680, 7400, 2345, 1111], [[2, 4, 50, False]], 2000],
   [[3680, 7400, 2000, 1111], 345]],
  ['regression: curtailed energy sign (partial repair)',
   [[7400, 1111, 3680, 11000, 1000, 11000, 1380, 3333, 0, 11000, 0],
    [[4, 8, 0, False], [8, 11, 50, True]], 0],
   [[7400, 1111, 3680, 11000, 0, 0, 0, 0, 0, 11000, 0], 16713]],
  ['control 1',
   [[3680, 1000, 3680, 1000, 3333, 2345, 1380, 1380, 1000, 3680, 7400],
    [[6, 11, 25, True], [5, 10, 75, False]], 0],
   [[3680, 1000, 3680, 1000, 3333, 1758, 1035, 1035, 750, 2760, 7400], 2447]],
  ['control 2',
   [[7400, 3680, 7400, 3333, 0, 1380, 1111, 3333, 3680, 7400, 1111, 1380],
    [[0, 3, 75, True], [0, 3, 50, False]], 0],
   [[3700, 1840, 3700, 3333, 0, 1380, 1111, 3333, 3680, 7400, 1111, 1380], 9240]]],
 [['boundary: event ends at slot', [[3680, 3680, 3680], [[0, 1, 50, False]], 0],
   [[1840, 3680, 3680], 1840]],
  ['boundary: opted-out event', [[7400, 7400], [[0, 2, 0, True]], 1380], [[7400, 7400], 0]],
  ['boundary: plan below floor', [[1000, 7400], [[0, 2, 0, False]], 1380], [[1000, 1380], 6020]],
  ['regression: curtailed energy sign',
   [[1380, 1380, 1111, 2345, 1380, 2345], [[6, 11, 0, False], [3, 7, 60, False], [3, 6, 0, False]],
    0],
   [[1380, 1380, 1111, 0, 0, 0], 6070]],
  ['regression: curtailed energy sign (partial repair)',
   [[2345, 7400, 3680, 3333, 7400, 3680], [[2, 4, 60, False], [1, 5, 0, True], [5, 10, 25, False]],
    2000],
   [[2345, 7400, 2208, 2000, 7400, 2000], 4485]],
  ['control 1',
   [[0, 1000, 1000, 2345, 0, 3680, 1380, 3680], [[4, 8, 50, True], [5, 10, 75, True]], 0],
   [[0, 1000, 1000, 2345, 0, 3680, 1380, 3680], 0]],
  ['control 2',
   [[3333, 7400, 1000, 2345, 11000, 2345], [[3, 7, 50, False], [5, 6, 25, True]], 2000],
   [[3333, 7400, 1000, 2000, 5500, 2000], 6190]]],
 [['boundary: event ends at slot', [[3680, 3680, 3680], [[0, 1, 50, False]], 0],
   [[1840, 3680, 3680], 1840]],
  ['boundary: opted-out event', [[7400, 7400], [[0, 2, 0, True]], 1380], [[7400, 7400], 0]],
  ['boundary: plan below floor', [[1000, 7400], [[0, 2, 0, False]], 1380], [[1000, 1380], 6020]],
  ['regression: curtailed energy sign',
   [[0, 3333, 3333, 0, 1380, 2345, 1111, 11000, 0],
    [[7, 11, 25, False], [3, 4, 0, True], [3, 6, 0, True]], 2000],
   [[0, 3333, 3333, 0, 1380, 2345, 1111, 2750, 0], 8250]],
  ['regression: curtailed energy sign (partial repair)',
   [[11000, 1380, 3333, 3333, 1111, 1380, 11000, 11000, 2345, 1111],
    [[5, 9, 60, True], [4, 5, 60, False], [1, 6, 0, False]], 2000],
   [[11000, 1380, 2000, 2000, 1111, 1380, 11000, 11000, 2345, 1111], 2666]],
  ['control 1',
   [[3680, 3680, 1000, 0, 3333, 1000, 3333, 3680],
    [[1, 5, 0, False], [7, 11, 25, False], [6, 6, 60, False]], 2000],
   [[3680, 2000, 1000, 0, 2000, 1000, 3333, 2000], 4693]],
  ['control 2',
   [[1380, 7400, 7400, 1000, 1111, 2345, 1380], [[4, 8, 0, False], [6, 10, 0, False]], 0],
   [[1380, 7400, 7400, 1000, 0, 0, 0], 4836]]],
 [['boundary: event ends at slot', [[3680, 3680, 3680], [[0, 1, 50, False]], 0],
   [[1840, 3680, 3680], 1840]],
  ['boundary: opted-out event', [[7400, 7400], [[0, 2, 0, True]], 1380], [[7400, 7400], 0]],
  ['boundary: plan below floor', [[1000, 7400], [[0, 2, 0, False]], 1380], [[1000, 1380], 6020]],
  ['regression: curtailed energy sign',
   [[0, 2345, 2345, 1000, 11000, 0, 11000, 0, 11000, 1111, 1380, 0],
    [[5, 10, 60, False], [11, 15, 0, True], [5, 9, 25, False]], 2000],
   [[0, 2345, 2345, 1000, 11000, 0, 2750, 0, 2750, 1111, 1380, 0], 16500]],
  ['regression: curtailed energy sign (partial repair)',
   [[1000, 2345, 1111, 1111, 1111, 1380, 1380, 2345],
    [[4, 8, 50, False], [4, 4, 75, True], [0, 5, 25, False]], 2000],
   [[1000, 2000, 1111, 1111, 1111, 1380, 1380, 2000], 690]],
  ['control 1', [[3333, 0, 1000, 1111, 1380, 7400, 1380, 7400, 3680], [[5, 10, 0, True]], 1380],
   [[3333, 0, 1000, 1111, 1380, 7400, 1380, 7400, 3680], 0]],
  ['control 2', [[2345, 7400, 1111, 3333, 3333, 7400, 3680], [[5, 8, 25, False]], 0],
   [[2345, 7400, 1111, 3333, 3333, 1850, 920], 8310]]]]
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
boundary: event ends at slot[[1840, 3680, 3680], -1840][[1840, 3680, 3680], 1840]Failed
boundary: opted-out event[[7400, 7400], 0][[7400, 7400], 0]Passed
boundary: plan below floor[[1000, 1380], -6020][[1000, 1380], 6020]Failed
regression: curtailed energy sign[[11000, 1000, 7400, 1380, 2345, 1380, 4440, 4440, 1111], -5920][[11000, 1000, 7400, 1380, 2345, 1380, 4440, 4440, 1111], 5920]Failed
regression: curtailed energy sign (partial repair)[[1380, 1000, 3333, 2345, 1000, 1380, 11000, 3333, 2208, 0], -1472][[1380, 1000, 3333, 2345, 1000, 1380, 11000, 3333, 2208, 0], 1472]Failed
control 1[[1000, 3333, 1111, 1380, 2750], -8250][[1000, 3333, 1111, 1380, 2750], 8250]Failed
control 2[[1380, 1000, 1111, 1000, 1000, 2000, 2000, 7400, 1111, 2208, 6600, 1111], -8538][[1380, 1000, 1111, 1000, 1000, 2000, 2000, 7400, 1111, 2208, 6600, 1111], 8538]Failed

SHA-256 / a1e7938c35c8e003c2dd090df829f3aa0d00410f7ee3ee2586b179d8c11491f4

2 / The unsuccessful fix

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

N = 1
observations = []
def solve(profile, events, floor_w):
    out = []
    for t, p in enumerate(profile):
        pct = 100
        for s, e, q, opt in events:
            if opt:
                continue
            if s <= t < e and q < pct:
                pct = q
        new = p * pct // 100
        new = max(new, min(p, floor_w))
        out.append(new)
    return [out, len([1 for p, n in zip(profile, out) if n < p])]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['boundary: event ends at slot', [[3680, 3680, 3680], [[0, 1, 50, False]], 0],
   [[1840, 3680, 3680], 1840]],
  ['boundary: opted-out event', [[7400, 7400], [[0, 2, 0, True]], 1380], [[7400, 7400], 0]],
  ['boundary: plan below floor', [[1000, 7400], [[0, 2, 0, False]], 1380], [[1000, 1380], 6020]],
  ['regression: curtailed energy sign',
   [[11000, 1000, 7400, 1380, 2345, 1380, 7400, 7400, 1111],
    [[8, 13, 50, False], [5, 8, 60, False]], 2000],
   [[11000, 1000, 7400, 1380, 2345, 1380, 4440, 4440, 1111], 5920]],
  ['regression: curtailed energy sign (partial repair)',
   [[1380, 1000, 3333, 2345, 1000, 1380, 11000, 3333, 3680, 0],
    [[8, 9, 60, False], [9, 10, 25, True], [4, 9, 75, True]], 0],
   [[1380, 1000, 3333, 2345, 1000, 1380, 11000, 3333, 2208, 0], 1472]],
  ['control 1',
   [[1000, 3333, 1111, 1380, 11000], [[1, 2, 75, True], [5, 8, 75, False], [4, 5, 25, False]], 0],
   [[1000, 3333, 1111, 1380, 2750], 8250]],
  ['control 2',
   [[1380, 1000, 1111, 1000, 1000, 3333, 3333, 7400, 1111, 3680, 11000, 1111],
    [[8, 12, 60, False], [5, 7, 0, False]], 2000],
   [[1380, 1000, 1111, 1000, 1000, 2000, 2000, 7400, 1111, 2208, 6600, 1111], 8538]]],
 [['boundary: event ends at slot', [[3680, 3680, 3680], [[0, 1, 50, False]], 0],
   [[1840, 3680, 3680], 1840]],
  ['boundary: opted-out event', [[7400, 7400], [[0, 2, 0, True]], 1380], [[7400, 7400], 0]],
  ['boundary: plan below floor', [[1000, 7400], [[0, 2, 0, False]], 1380], [[1000, 1380], 6020]],
  ['regression: curtailed energy sign', [[3680, 7400, 2345, 1111], [[2, 4, 50, False]], 2000],
   [[3680, 7400, 2000, 1111], 345]],
  ['regression: curtailed energy sign (partial repair)',
   [[7400, 1111, 3680, 11000, 1000, 11000, 1380, 3333, 0, 11000, 0],
    [[4, 8, 0, False], [8, 11, 50, True]], 0],
   [[7400, 1111, 3680, 11000, 0, 0, 0, 0, 0, 11000, 0], 16713]],
  ['control 1',
   [[3680, 1000, 3680, 1000, 3333, 2345, 1380, 1380, 1000, 3680, 7400],
    [[6, 11, 25, True], [5, 10, 75, False]], 0],
   [[3680, 1000, 3680, 1000, 3333, 1758, 1035, 1035, 750, 2760, 7400], 2447]],
  ['control 2',
   [[7400, 3680, 7400, 3333, 0, 1380, 1111, 3333, 3680, 7400, 1111, 1380],
    [[0, 3, 75, True], [0, 3, 50, False]], 0],
   [[3700, 1840, 3700, 3333, 0, 1380, 1111, 3333, 3680, 7400, 1111, 1380], 9240]]],
 [['boundary: event ends at slot', [[3680, 3680, 3680], [[0, 1, 50, False]], 0],
   [[1840, 3680, 3680], 1840]],
  ['boundary: opted-out event', [[7400, 7400], [[0, 2, 0, True]], 1380], [[7400, 7400], 0]],
  ['boundary: plan below floor', [[1000, 7400], [[0, 2, 0, False]], 1380], [[1000, 1380], 6020]],
  ['regression: curtailed energy sign',
   [[1380, 1380, 1111, 2345, 1380, 2345], [[6, 11, 0, False], [3, 7, 60, False], [3, 6, 0, False]],
    0],
   [[1380, 1380, 1111, 0, 0, 0], 6070]],
  ['regression: curtailed energy sign (partial repair)',
   [[2345, 7400, 3680, 3333, 7400, 3680], [[2, 4, 60, False], [1, 5, 0, True], [5, 10, 25, False]],
    2000],
   [[2345, 7400, 2208, 2000, 7400, 2000], 4485]],
  ['control 1',
   [[0, 1000, 1000, 2345, 0, 3680, 1380, 3680], [[4, 8, 50, True], [5, 10, 75, True]], 0],
   [[0, 1000, 1000, 2345, 0, 3680, 1380, 3680], 0]],
  ['control 2',
   [[3333, 7400, 1000, 2345, 11000, 2345], [[3, 7, 50, False], [5, 6, 25, True]], 2000],
   [[3333, 7400, 1000, 2000, 5500, 2000], 6190]]],
 [['boundary: event ends at slot', [[3680, 3680, 3680], [[0, 1, 50, False]], 0],
   [[1840, 3680, 3680], 1840]],
  ['boundary: opted-out event', [[7400, 7400], [[0, 2, 0, True]], 1380], [[7400, 7400], 0]],
  ['boundary: plan below floor', [[1000, 7400], [[0, 2, 0, False]], 1380], [[1000, 1380], 6020]],
  ['regression: curtailed energy sign',
   [[0, 3333, 3333, 0, 1380, 2345, 1111, 11000, 0],
    [[7, 11, 25, False], [3, 4, 0, True], [3, 6, 0, True]], 2000],
   [[0, 3333, 3333, 0, 1380, 2345, 1111, 2750, 0], 8250]],
  ['regression: curtailed energy sign (partial repair)',
   [[11000, 1380, 3333, 3333, 1111, 1380, 11000, 11000, 2345, 1111],
    [[5, 9, 60, True], [4, 5, 60, False], [1, 6, 0, False]], 2000],
   [[11000, 1380, 2000, 2000, 1111, 1380, 11000, 11000, 2345, 1111], 2666]],
  ['control 1',
   [[3680, 3680, 1000, 0, 3333, 1000, 3333, 3680],
    [[1, 5, 0, False], [7, 11, 25, False], [6, 6, 60, False]], 2000],
   [[3680, 2000, 1000, 0, 2000, 1000, 3333, 2000], 4693]],
  ['control 2',
   [[1380, 7400, 7400, 1000, 1111, 2345, 1380], [[4, 8, 0, False], [6, 10, 0, False]], 0],
   [[1380, 7400, 7400, 1000, 0, 0, 0], 4836]]],
 [['boundary: event ends at slot', [[3680, 3680, 3680], [[0, 1, 50, False]], 0],
   [[1840, 3680, 3680], 1840]],
  ['boundary: opted-out event', [[7400, 7400], [[0, 2, 0, True]], 1380], [[7400, 7400], 0]],
  ['boundary: plan below floor', [[1000, 7400], [[0, 2, 0, False]], 1380], [[1000, 1380], 6020]],
  ['regression: curtailed energy sign',
   [[0, 2345, 2345, 1000, 11000, 0, 11000, 0, 11000, 1111, 1380, 0],
    [[5, 10, 60, False], [11, 15, 0, True], [5, 9, 25, False]], 2000],
   [[0, 2345, 2345, 1000, 11000, 0, 2750, 0, 2750, 1111, 1380, 0], 16500]],
  ['regression: curtailed energy sign (partial repair)',
   [[1000, 2345, 1111, 1111, 1111, 1380, 1380, 2345],
    [[4, 8, 50, False], [4, 4, 75, True], [0, 5, 25, False]], 2000],
   [[1000, 2000, 1111, 1111, 1111, 1380, 1380, 2000], 690]],
  ['control 1', [[3333, 0, 1000, 1111, 1380, 7400, 1380, 7400, 3680], [[5, 10, 0, True]], 1380],
   [[3333, 0, 1000, 1111, 1380, 7400, 1380, 7400, 3680], 0]],
  ['control 2', [[2345, 7400, 1111, 3333, 3333, 7400, 3680], [[5, 8, 25, False]], 0],
   [[2345, 7400, 1111, 3333, 3333, 1850, 920], 8310]]]]
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
boundary: event ends at slot[[1840, 3680, 3680], 1][[1840, 3680, 3680], 1840]Failed
boundary: opted-out event[[7400, 7400], 0][[7400, 7400], 0]Passed
boundary: plan below floor[[1000, 1380], 1][[1000, 1380], 6020]Failed
regression: curtailed energy sign[[11000, 1000, 7400, 1380, 2345, 1380, 4440, 4440, 1111], 2][[11000, 1000, 7400, 1380, 2345, 1380, 4440, 4440, 1111], 5920]Failed
regression: curtailed energy sign (partial repair)[[1380, 1000, 3333, 2345, 1000, 1380, 11000, 3333, 2208, 0], 1][[1380, 1000, 3333, 2345, 1000, 1380, 11000, 3333, 2208, 0], 1472]Failed
control 1[[1000, 3333, 1111, 1380, 2750], 1][[1000, 3333, 1111, 1380, 2750], 8250]Failed
control 2[[1380, 1000, 1111, 1000, 1000, 2000, 2000, 7400, 1111, 2208, 6600, 1111], 4][[1380, 1000, 1111, 1000, 1000, 2000, 2000, 7400, 1111, 2208, 6600, 1111], 8538]Failed

SHA-256 / 479a20dac939e8cb71e79f1f69dfc7a5bcbea468c55cdee7a726e3677b07a52b

HELD IN THE MEMBER ARCHIVE

The verified repair and its recorded checks are member-only.

This mechanism has 7 recorded checks per implementation. The open-access tier publishes the failure and the unsuccessful fix; the repaired source that passes every check, and the observations that prove it, are available to members.

Every case sharing this mechanism uses the same contract and the same repair, so this one record is held back for all of them.

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Verification & scope

Deterministic stipulated toy contract for teaching; no claim of conformance with any standard, vendor protocol or production controller. 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 2026-09-29T14:51:52.950606+00:00.

Case digest / c69052f3156b5a89fba73d2e518f065ac28f0013e626b8815bb288f919d7dc1f