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molaR (version 2.1)

DNE: Calculate Dirichlet normal energy of a surface

Description

A function that calculates Dirichlet normal energy following the method of Bunn et al. (2011) Comparing Dirichlet normal surface energy of tooth crowns, a new technique of molar shape quantification for dietary inference, with previous methods in isolation and in combination. Am J Phys Anthropol 145:247-261 doi: 10.1002 ajpa.21489

Usage

DNE(plyFile, outliers = 0.1)

Arguments

plyFile
An object of class 'mesh3d' and 'shape3d' with calculated normals
outliers
The percentile of Dirichlet energy density values to be excluded defaults to top 0.1 percent

Details

The function requires an object created by reading in a ply file utilizing either the read.ply or the read.AVIZO.ply function, with calculated normals.

Dirichlet normal energy is calculated on meshes that represent specimen surfaces and have already been simplified to 10,000 faces and pre-smoothed in a 3D data editing program.

The function does not include boundary vertices in the calculation, and therefore the analyzed surface cannot be closed (i.e., it must contain a hole). The function defaults to remove the top 0.1 percent of calculated energy densities as outliers. Mesh orientation does not affect for this calculation.