Function to find the boundaries of a convex set

Description

Finds the boundaries of a bounded convex set along a specified straight line, using a bisection approach. It is mainly intended for use within arms.

Usage

convex.bounds(x, dir, indFunc, ..., tol=1e-07)

Arguments

Details

Uses a bisection algorithm along a line having parametric representation x + t * dir.

Value

A two dimensional vector ans. The boundaries of the set are x + ans[1] * dir and x + ans[2] * dir.

Author(s)

Giovanni Petris GPetris@uark.edu

Examples

## boundaries of a unit circle
convex.bounds(c(0,0), c(1,1), indFunc=function(x) crossprod(x)<1)

Results

R version 3.3.1 (2016-06-21) -- "Bug in Your Hair"
Copyright (C) 2016 The R Foundation for Statistical Computing
Platform: x86_64-pc-linux-gnu (64-bit)

R is free software and comes with ABSOLUTELY NO WARRANTY.
You are welcome to redistribute it under certain conditions.
Type 'license()' or 'licence()' for distribution details.

R is a collaborative project with many contributors.
Type 'contributors()' for more information and
'citation()' on how to cite R or R packages in publications.

Type 'demo()' for some demos, 'help()' for on-line help, or
'help.start()' for an HTML browser interface to help.
Type 'q()' to quit R.

> library(HI)
> png(filename="/home/ddbj/snapshot/RGM3/R_CC/result/HI/convex.bounds.Rd_%03d_medium.png", width=480, height=480)
> ### Name: convex.bounds
> ### Title: Function to find the boundaries of a convex set
> ### Aliases: convex.bounds
> ### Keywords: misc
> 
> ### ** Examples
> 
> ## boundaries of a unit circle
> convex.bounds(c(0,0), c(1,1), indFunc=function(x) crossprod(x)<1)
[1] -0.7071068  0.7071068
> 
> 
> 
> 
> 
> dev.off()
null device 
          1 
>