compressStrucGlmer: Compress strucGlmer object

In stevencarlislewalker/lme4ord: Generalized Linear Mixed Models with Flexible (Co)Variance Structures

Description

This feature is not yet written, but is important enough that current design decisions should reflect it's future possibility. This proposal will help reduce the costs of keeping redundant information in strucGlmer objects. The idea is to store various components on disk, and then only retreive them when necessary. This will require very consistent use of extractor functions that have versions that can take a filename or connection and retreive the component that way.

Usage

compressStrucGlmer(object, components, ...)

Arguments

object	a strucGlmer object.
components	components to compress.
...	not used yet.

Value

an error message pointing to this help page.

What kind of redundancy are we talking about?

strucGlmer objects contain a strucParseFormula object and a deviance function. The environment of this deviance function contains many objects, some of which are essentially replicated in the parsed formula object. In particular, the matrices in the parsed formula are strucMatrix objects whereas the matrices in the environment of the deviance function are Matrix package objects linked to C++ objects through external pointers.

Why do we want redundancy?

This redundancy makes the output module code easier to maintain, while retaining a fast optimization module. In partiular, the strucMatrix objects in the parsed formula make it easier to write consistent and reuseable code, whereas the Matrix/C++ objects in the environment of the deviance function facilitate relatively fast linear algebra.

stevencarlislewalker/lme4ord documentation built on May 30, 2019, 4:43 p.m.