aggregate_spectra: Aggregates spectral and data information

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

Description

Aggregates spectral and data information of a Spectra object using a user-defined function.

Details

Aggregates the spectral information of a Spectra object using an aggregation function chosen by the user.

There is two distinct function for Spectra and SpectraDataFrame classes. For SpectraDataFrame objects, associated data is also aggregated using the function provided by the fun option. Additionally, the method for SpectraDataFrame has an id option that allows to specify an attribute which will be used to split the object, apply sequentially the fun function, and recombine the results in an unique object.

Value

An object of the same class as obj

Methods

x=Spectra

aggregate_spectra(obj, fun=mean, ...)

	obj	A Spectra object
	fun	An aggregation function
	...	Expressions evaluated in the context of fun

x=SpectraDataFrame

aggregate_spectra(obj, fun=mean, id=NULL, ...)

	obj	A SpectraDataFrame object
	fun	An aggregation function
	id	Attribute(s) to split the object (character vector)
	...	Expressions evaluated in the context of fun

Author(s)

Pierre Roudier [e-mail]

See Also

apply_spectra

Examples

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

# Aggregation on the whole collection
m <- aggregate_spectra(australia, fun = mean)
summary(m)
plot(m)

# Aggregation factor-wise
australia$fact <- sample(LETTERS[1:3], size = nrow(australia), replace = TRUE) # Generate some kind of factor
summary(australia)
m <- aggregate_spectra(australia, fun = mean, id = 'fact')
summary(m)
plot(m)

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