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process_stability_index

process_stability_index ¤

ProcessStabilityIndex ¤

ProcessStabilityIndex(
    dataframe: DataFrame,
    signal_uuid: str,
    *,
    target: Optional[float] = None,
    lower_spec: Optional[float] = None,
    upper_spec: Optional[float] = None,
    event_uuid: str = "eng:stability_index",
    value_column: str = "value_double",
    time_column: str = "systime"
)

Bases: Base

Engineering: Process Stability Index

Generate a single 0-100 stability score per shift/day for a signal. Answers 'is my process running well today?' with one number.

Methods: - stability_score: Composite 0-100 score per window. - score_trend: Is stability improving or degrading? - worst_periods: N worst-scoring windows. - stability_comparison: Compare each window to best-observed.

stability_score ¤

stability_score(window: str = '8h') -> pd.DataFrame

Composite 0-100 stability score per window.

Four sub-scores (each 0-25): - variance_score: low std = high score - bias_score: on-target = high score - excursion_score: in-spec = high score - smoothness_score: low point-to-point jitter = high score

Returns:

Type Description
DataFrame

DataFrame with columns: window_start, stability_score,

DataFrame

variance_score, bias_score, excursion_score, smoothness_score,

DataFrame

grade.

score_trend ¤

score_trend(
    window: str = "8h", n_windows: int = 7
) -> pd.DataFrame

Track whether stability is improving or degrading.

Returns:

Type Description
DataFrame

DataFrame with columns: window_start, stability_score,

DataFrame

rolling_avg, trend_direction, score_change.

worst_periods ¤

worst_periods(
    window: str = "1h", n: int = 5
) -> pd.DataFrame

Return the N worst-scoring windows.

Returns:

Type Description
DataFrame

DataFrame with columns: window_start, stability_score,

DataFrame

variance_score, bias_score, excursion_score, smoothness_score,

DataFrame

primary_issue.

stability_comparison ¤

stability_comparison(window: str = '8h') -> pd.DataFrame

Compare each window to the best-observed window.

Returns:

Type Description
DataFrame

DataFrame with columns: window_start, stability_score,

DataFrame

best_score, gap_to_best, pct_of_best.