Statistical Process Control (mqr.spc)

User guide

Statistical Process Control

Detailed examples

nklsxn/mqrpy-guide

This module provides classes for statistical process control. It is designed for use with mqr.plot.spc, which provides plotting routines for the types defined in this module. The module can also be used independently of control charts, for example in scripts that detect alarm conditions and take some action.

Classes

These are superclasses that define the behaviour of chart parameters and statistics.

ControlParams()	Base class of all control methods.
ShewhartParams()	Base class of Shewhart-type control methods.
ControlStatistic(stat, nobs)	Monitored statistic of a controlled process.

These are subclasses of ControlParams. Users can define new control parameters by subclassing ControlParams or ShewhartParams.

XBarParams(centre, sigma[, nsigma, name])	XBar (sample mean) control parameters.
RParams(centre, sigma[, nsigma, name])	R (sample range) control parameters.
SParams(centre[, nsigma, name])	S (sample standard deviation) control parameters.
EwmaParams(mu_0, sigma, lmda, L[, ...])	EWMA control parameters.
MewmaParams(mu, cov, lmda, limit[, name])	MEWMA (multivaraite-EMWA) control parameters.

Submodules

These submodules define alarm rules and other utilities, including unbiasing constants.

rules	SPC alarm rules (mqr.spc.rules)
util	SPC utilities (mqr.spc.util)