tsdive.spc ¶

spc(
    archive: str | Path,
    baseline: str,
    window: str,
    *,
    basis: str
    | CalculationBasis = CalculationBasis.TIME_WEIGHTED,
    stepped: bool = False,
) -> SpcAnalysis

Chart one window of a single-tag archive against baseline limits.

Parameters:

Name	Type	Description	Default
`archive`	`str \| Path`	parquet archive carrying `tsdive.meta`.	required
`baseline`	`str`	`START/END` in ISO 8601 UTC the limits are computed from.	required
`window`	`str`	`START/END` in ISO 8601 UTC to chart.	required
`basis`	`str \| CalculationBasis`	calculation basis declared on the read.	`TIME_WEIGHTED`
`stepped`	`bool`	stepped interpolation between samples.	`False`

Raises:

Type	Description
`ValueError`	malformed window, overlapping windows.
`TSDiveError`	a censored baseline, or any typed refusal from the read path.

Examples:

>>> import tsdive
>>> c = tsdive.spc("data/demo/fic101_demo.parquet",
...                "2024-03-30T20:00:00Z/2024-03-31T01:00:00Z",  # baseline
...                "2024-03-31T01:00:00Z/2024-03-31T06:00:00Z")  # window
>>> round(c.limits.lcl, 3), round(c.limits.center, 3), round(c.limits.ucl, 3)
(60.673, 62.319, 63.966)
>>> c.frame["rule"].value_counts().to_dict()
{'BEYOND_3SIGMA': 29, 'RUN_9_SAMESIDE': 6, 'TREND_6': 2}