xtabs {BiocGenerics}R Documentation

Cross tabulation

Description

xtabs creates a contingency table (optionally a sparse matrix) from cross-classifying factors, usually contained in a data-frame-like object, using a formula interface.

NOTE: This man page is for the xtabs S4 generic function defined in the BiocGenerics package. See ?stats::xtabs for the default method (defined in the stats package). Bioconductor packages can define specific methods for objects not supported by the default method.

Usage

xtabs(formula=~., data=parent.frame(), subset, sparse=FALSE, 
      na.action, exclude=c(NA, NaN), drop.unused.levels=FALSE)

Arguments

formula, subset, sparse, na.action, exclude, drop.unused.levels

See ?stats::xtabs for a description of these arguments.

data

A data-frame-like R object.

Value

See ?stats::xtabs for the value returned by the default method.

Specific methods defined in other Bioconductor packages should also return the type of object returned by the default method.

See Also

stats::xtabs for the default xtabs method.

showMethods for displaying a summary of the methods defined for a given generic function.

selectMethod for getting the definition of a specific method.

xtabs,DataTable-method in the IRanges package for the method defined for DataTable objects.

BiocGenerics for a summary of all the generics defined in the BiocGenerics package.

Examples

xtabs  # note the dispatch on the 'data' arg only
showMethods("xtabs")
selectMethod("xtabs", "ANY")  # the default method

[Package BiocGenerics version 0.2.0 Index]