segmentBins: Segments normalized copy number data

Description Usage Arguments Value Parallel processing Author(s) See Also Examples

Description

Segments normalized copy number data.

Usage

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segmentBins(object, smoothBy=FALSE, alpha=1e-10, undo.splits="sdundo", undo.SD=1,
  force=FALSE, transformFun="log2", ...)

Arguments

object

An object of class QDNAseqCopyNumbers.

smoothBy

An optional integer value to perform smoothing before segmentation by taking the mean of every smoothBy bins, and then segment those means. Default (FALSE) is to perform no smoothing. smoothBy=1L is a special case that will not perform smoothing, but will split the segmentation process by chromosome instead of by sample.

alpha

Significance levels for the test to accept change-points. Default is 1e-10.

undo.splits

A character string specifying how change-points are to be undone, if at all. Default is "sdundo", which undoes splits that are not at least this many SDs apart. Other choices are "prune", which uses a sum of squares criterion, and "none".

undo.SD

The number of SDs between means to keep a split if undo.splits="sdundo". Default is 1.0.

force

Whether to force execution when it causes removal of downstream calling results.

transformFun

A function to transform the data with. This can be the default "log2" for log2(x + .Machine$double.xmin), "sqrt" for the Anscombe transform of sqrt(x * 3/8) which stabilizes the variance, "none" for no transformation, or any R function that performs the desired transformation and also its inverse when called with parameter inv=TRUE.

...

Additional arguments passed to segment.

Value

Returns an object of class QDNAseqCopyNumbers with segmentation results added.

Parallel processing

This function uses future to segment samples in parallel.

Author(s)

Ilari Scheinin

See Also

Internally, segment of the DNAcopy package, which implements the CBS method, is used to segment the data.

Examples

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 data(LGG150)
 readCounts <- LGG150
 readCountsFiltered <- applyFilters(readCounts)
 readCountsFiltered <- estimateCorrection(readCountsFiltered)
 copyNumbers <- correctBins(readCountsFiltered)
 copyNumbersNormalized <- normalizeBins(copyNumbers)
 copyNumbersSmooth <- smoothOutlierBins(copyNumbersNormalized)
 copyNumbersSegmented <- segmentBins(copyNumbersSmooth)
 

QDNAseq documentation built on Nov. 8, 2020, 6:57 p.m.