convCP: Convert Contour Lines into a PolySet

Description Usage Arguments Details Value Author(s) See Also Examples

View source: R/PBSmapping.r

Description

Convert output from contourLines into a PolySet.

Usage

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convCP (data, projection = NULL, zone = NULL)

Arguments

data

contour line data, often from the contourLines function.

projection

optional projection attribute to add to the PolySet.

zone

optional zone attribute to add to the PolySet.

Details

data contains a list as described below. The contourLines function create a list suitable for the data argument.

A three-element list describes each contour. The named elements in this list include the scalar level, the vector x, and the vector y. Vectors x and y must have equal lengths. A higher-level list (data) contains one or more of these contours lists.

Value

A list with two named elements PolySet and PolyData. The PolySet element contains a PolySet representation of the contour lines. The PolyData element links each contour line (PID, SID) with a level.

Author(s)

Nicholas M. Boers, Associate Professor – Computer Science
MacEwan University, Edmonton AB
Last modified Rd: 2013-04-10

See Also

contour, contourLines, convLP, makeTopography.

Examples

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local(envir=.PBSmapEnv,expr={
  oldpar = par(no.readonly=TRUE)
  #--- create sample data for the contourLines() function
  x <- seq(-0.5, 0.8, length=50);  y <- x
  z <- outer(x, y, FUN = function(x,y) { sin(2*pi*(x^2+y^2))^2; } )
  data <- contourLines(x, y, z, levels=c(0.2, 0.8))
  #--- pass that sample data into convCP()
  result <- convCP(data)
  #--- plot the result
  plotLines(result$PolySet, projection=1)
  print(result$PolyData)
  par(oldpar)
})

PBSmapping documentation built on Jan. 15, 2021, 3:41 p.m.