R: Calculate the area of a vowel space

Vowel space area functions {phonR} | R Documentation

## Calculate the area of a vowel space

### Description

Calculate the area of an `F2 x F1` vowel space, either as the area of a polygon connecting vowel formant means, or the area of a convex hull encompassing all tokens.

### Usage

        convexHullArea(f1, f2, group=NULL)
        vowelMeansPolygonArea(f1, f2, vowel, poly.order, group=NULL)

### Arguments

`f1` | Numeric vector of first formant frequencies.
`f2` | Numeric vector or second formant frequencies.
`vowel` | Vector or factor of vowel identifiers (typically a character vector, though numeric will work).
`poly.order` | Order in which the polygon vertices should be connected. Should contain each value in `vowel` once.
`group` | Vector or factor indicating groupings of points to fit separate convex hulls to. If `NULL` (the default), a single hull will be generated for all points.

### Author(s)

McCloy, Daniel drmccloy@uw.edu

### See Also

`chull`, `areapl`

### Examples

        data(indoVowels)
        hull.area <- with(indo, convexHullArea(f1, f2, group=subj))
        poly.area <- with(indo, vowelMeansPolygonArea(f1, f2, vowel,
            poly.order=c("i", "e", "a", "o", "u"), group=subj))

[Package phonR version 1.0-7 Index]