pairwise_indices: Pairwise indices

In spectrolab: Class and Methods for Spectral Data

Pairwise indices

Description

pairwise_indices computes pairwise spectral indices. Indices are computed as (a - b) / (a + b) where a is the lower band. The column names of the resulting matrix are given as "a|b".

Usage

pairwise_indices(x, max_out_elements = 5e+08)

Arguments

x	spectra
max_out_elements	maximum number of elements in the output object

Value

list that includes the *indices* between bands a and b (column names a|b) and the pairwise *band_combinations*

Author(s)

Jose Eduardo Meireles

Examples

library(spectrolab)
spec  = as_spectra(spec_matrix_example, name_idx = 1)

# Resampling spectra since a spectral dataset with 2,001 bands
# results in 2,001,000 unique spectral indices per sample
new_bands = seq(400, 2400, 10)
spec = resample(spec, new_bands, make_fwhm(spec, new_bands) )
p_idx = pairwise_indices(spec)

spectrolab documentation built on April 3, 2025, 9:33 p.m.