dist_pairs_map: Creats a map of the distance between pairs of fatty acid...

In qfasar: Quantitative Fatty Acid Signature Analysis in R

Description

The utility function dist_pairs_map computes the distance between all possible pairs of fatty acid signatures within each type of prey or predator.

Usage

dist_pairs_map(sig_data, dist_meas = 1, gamma = 1)

Arguments

sig_data	A numeric matrix of fatty acid signatures in column-major format.
dist_meas	An integer indicator of the distance measure to compute. Default value 1.
gamma	The power parameter of the chi-square distance measure. Default value 1.

Value

A list containing the following elements:

n_sig

The number of signatures (columns) in sig_data.

sig_1

The column of sig_data containing one signature.

sig_2

The column of sig_data containing the other signature.

dist

The distance between signatures sig_1 and sig_2.

Details

This is an internal utility function. The signature data in sig_data are presumed to be ready for analysis, which is best accomplished by a call to the function prep_sig. Consequently, to increase execution speed during simulations, no numeric error checking is performed. Please refer to the documentation for prep_sig for additional information.

Please refer to the documentation for dist_between_2_sigs for additional information regarding distance measures.

Storing the distances between all possible pairs of fatty acid signatures along with the locations of each pair requires less memory than a square matrix of all possible pairs, while allowing the location of the signatures to be easily determined.

Utility functions called by dist_sigs_2_mean:

• dist_between_2_sigs

qfasar documentation built on March 20, 2020, 1:10 a.m.