splitBy {doBy}R Documentation

Split a data frame

Description

This is essentially a wrapper for the 'split' function, - the important difference being that variables to order by can be given by a model formula.

Usage

splitBy(formula, data = parent.frame(), drop=TRUE, return.matrix=FALSE)
## S3 method for class 'splitByData':
print(x, ...)

Arguments

formula The right hand side of a formula
data A data frame
drop Logical indicating if levels that do not occur should be dropped
return.matrix Should the returned list consist of dataframs or matrices, see 'details' below
x A splitByData object (basically a list).
... Additional arguments, currently not used.

Details

The funcion transform the dataframe 'data' into a numerical matrix (using the 'asNumericMatrix' function from the Hmisc package) and makes the splitting operation on this. If return.matrix is TRUE, then these matrices are returned, otherwise the matrices are turned into dataframes and then these are returned.

Value

A list of dataframes of matrices

Author(s)

Søren Højsgaard, sorenh@agrsci.dk

See Also

orderBy, summaryBy, transformBy, lapplyBy,

Examples

data(dietox)
splitBy(formula = ~Evit+Cu, data = dietox)

[Package doBy version 3.7 Index]