# fixBound: Fix the Boundary Points of a PolySet In PBSmapping: Mapping Fisheries Data and Spatial Analysis Tools

## Description

The ranges of a PolySet's X and Y columns define its boundary. This function fixes a PolySet's vertices by moving vertices near a boundary to the actual boundary.

## Usage

 1 fixBound (polys, tol)

## Arguments

 polys PolySet to fix. tol vector (length 1 or 2) specifying a percentage of the ranges to use in defining near to a boundary. If tol has two elements, the first specifies the tolerance for the x-axis and the second the y-axis. If it has only one element, the function uses the same tolerance for both axes.

## Details

When moving vertices to a boundary, the function moves them strictly horizontally or vertically, as appropriate.

## Value

PolySet identical to the input, except for possible changes in the X and Y columns.

## Author(s)

Nicholas M. Boers, Associate Professor – Computer Science
MacEwan University, Edmonton AB

closePolys, fixPOS, isConvex, isIntersecting, PolySet.

## Examples

 1 2 3 4 5 6 7 8 9 10 11 12 13 local(envir=.PBSmapEnv,expr={ oldpar = par(no.readonly=TRUE) #--- set up a long horizontal and long vertical line to extend the plot's #--- limits, and then try fixing the bounds of a line in the top-left #--- corner and a line in the bottom-right corner polys <- data.frame(PID=c(1, 1, 2, 2, 3, 3, 4, 4), POS=c(1, 2, 1, 2, 1, 2, 1, 2), X = c(0, 10, 5, 5, 0.1, 4.9, 5.1, 9.9), Y = c(5, 5, 0, 10, 5.1, 9.9, 0.1, 4.9)) polys <- fixBound(polys, tol=0.0100001) plotLines(polys) par(oldpar) })

### Example output

sh: 1: cannot create /dev/null: Permission denied

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A complete user guide 'PBSmapping-UG.pdf' is located at
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Packaged on 2015-04-23
Pacific Biological Station, Nanaimo

All available PBS packages can be found at

To see demos, type '.PBSfigs()'.
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PBSmapping documentation built on Jan. 15, 2021, 3:41 p.m.