rLFT (version 1.0.1)

bct: Boundary Convexity Tool

Description

Calculates raw convexity, convexity index, and sinuosity of a given sf object and returns a data frame with all measurements for each step and feature. If provided, the data will also be output to a tab delimited file.

Usage

bct(sfDataObject, step, window, ridName = NULL, filename = "")

Arguments

sfDataObject

An sf Object containing shape file data.

step

A numeric describing the distance between measurements along an arc.

window

A numeric describing the diameter of the window used to measure convexity.

ridName

A character denoting the column name where the unique ID for each feature is stored in given sf object.

filename

A character denoting the name of the file you wish to output convexity data to in tab delimited format. Must have the .txt extension.

Value

The output of this function is a data.frame that contains all measurements for each step and feature.

Reference

Albeke, S.E. et al. <U+201C>Measuring boundary convexity at multiple spatial scales using a linear <U+201C>moving window<U+201D> analysis: an application to coastal river otter habitat selection.<U+201D> Landscape Ecology 25 (2010): 1575-1587. [linked phrase](https://link.springer.com/article/10.1007/s10980-010-9528-4)

Details

This function will reject any sf object with a geographic coordinate system, so consider projecting your features. Your sf object must be of either type LINESTRING, MULTILINESTRING, POLYGON, or MULTIPOLYGON. If a given POLYGON or MUTLIPOLYGON contains inner rings, they will be ignored. If a unique ID Column name is not provided, the function will generate a unique ID for each feature. The arguments step and window can be any non-negative numeric. The argument ridName MUST be a character indicating the name of the column in your sf object where the route id is stored.

Examples

# NOT RUN {
library(rLFT)
data("shpObject")
#store convexity output data in a variable 'outputTable'
outputTable <- bct(shpObject, step = 50, window = 100, ridName = "RID")

# }