chainsaw: Chainsaw - modify gds file by subsetting all nodes

In TJGorrie/bigmelon: Illumina methylation array analysis for large experiments

Chainsaw – modify gds file by subsetting all nodes

Description

Currently the '[' function for the gds.class objects used by bigmelon only subsets a single node. This function does more like what you would normally expect a subsetting function to do, it returns a subset of the entire object. It may in future be a replacement for '[.gds.class'.

Usage

chainsaw(gfile, i = "", j = "", v = FALSE, cleanup = TRUE)

Arguments

gfile	A gds.class object.
i	Specifies rows (ie probes) in the desired subset, similar to behaviour of '['
j	Specifies columns (ie sampless) in the desired subset, similar to behaviour of '['
v	If true, spew many messages.
cleanup	If true, run a cleanup function that can substantially reduce the file size.

Details

This function is intended for use in the preprocessing and QC phase of a DNA methylation workflow. For efficiency, bigmelon stores data in a file, and the gds.class object is a file handle. True to its name, chainsaw chops the underlying file, this is a side affect of the function and is not affected by assignment of the return value.

Value

a gds.class object. This is a handle to the same file that the gfile argument points to. It's not generally useful to have two handles to the same file, but it may make code more readable. In interactive use, if not assigned, the returned object is usefully pretty-printed.

TJGorrie/bigmelon documentation built on Oct. 13, 2023, 9:51 p.m.