aggspec: Aggregate reflectance spectra

Description

Combines spectra (by taking the average, for example) according to an index or a vector of identities.

Usage

aggspec(rspecdata, by = NULL, FUN = mean, trim = TRUE, na.rm = FALSE)

Arguments

rspecdata

(required) data frame, possibly of class rspec containing the spectra to be manipulated. If it contains a wavelength column named "wl", that column will be ignored.

(required) either a single value specifying the range of spectra within the data frame to be combined (for example, by = 3 indicates the function will be applied to groups of 3 consecutive columns in the spectra data frame); a vector containing identifications for the columns in the spectra data frame (in which case the function will be applied to each group of spectra sharing the same identification); or a list of vectors, e.g., by = list(sex, species).

FUN

the function to be applied to the groups of spectra. (defaults to mean)

trim

logical. if TRUE (default), the function will try to identify and remove numbers at the end of the names of the columns in the new rspec object.

na.rm

should NAs be reomved? Defaults to FALSE.

Value

A data frame of class rspec containing the spectra after applying the aggregating function.

References

Montgomerie R (2006) Analyzing colors. In: Hill G, McGraw K (eds) Bird coloration. Harvard University Press, Cambridge, pp 90-147.

Examples

Run this code

## Not run: ------------------------------------
# data(teal)
# 
# # Average every two spectra
# teal.sset1 <- aggspec(teal, by = 2)
# plot(teal.sset1)
# 
# # Create factor and average spectra by levels 'a' and 'b'
# ind <- rep(c('a', 'b'), times = 6)
# teal.sset2 <- aggspec(teal, by = ind)
# 
# plot(teal.sset2) 
## ---------------------------------------------