split: Split a Spectra* object using factors

In inspectr: Storing, manipulating and analysis spectroscopy and associated data in R.

Description

Splits a Spectra* object into groups using a factor, either a provided as a vector or as an attribute in the features of the object.

Usage

split(x, f, drop = FALSE, ...)

Arguments

x	Spectra object
f	either a vector of factors (for objects inheriting from Spectra), or the name or indice of an attribute in the data slot of an object inheriting from SpectraDataFrame
drop	ignored
...	further potential arguments passed to methods.

Details

This is an adaptation of the split function in the base package.

Value

A list of objects of same class as x.

Author(s)

Pierre Roudier [e-mail]

See Also

separate, melt_spectra, lapply, and the l*pply family of function inthe plyr package.

Examples

# Loading example data
data(australia)
spectra(australia) <- sr_no ~ ... ~ 350:2500

# On a Spectra object, we need to provide a vector of factors
# to split the object
s <- as(australia, 'Spectra')
# We make up some kind of factor to split the data. 
idx <- sample(letters[1:5], replace = TRUE, size = nrow(s)) # This is a vector
r <- split(s, idx)
str(r)

# On a SpectradataFrame object, we can also provide the name or index 
# of an attribute
australia$fact <- sample(LETTERS[1:3], size = nrow(australia), replace = TRUE) # Generate some kind of factor
summary(australia)
r <- split(australia, 'fact')
str(r)

# A list is returned, and is thus ready for use with lapply, or any
# of the l*ply functions from the plyr package
lapply(r, nrow)

inspectr documentation built on May 2, 2019, 5:45 p.m.