Okay, been working with tripack, seems the most mature package for this. Got it to work well with their test data set - data(tritest). When i tried random numbers to explore further, i am getting some results that don't reconcile. example run this: library(tripack) y <- runif(100) x <- runif(100) vm <- voronoi.mosaic(x,y) plot(vm) par(new=T) plot(x,y,col='blue') when you look at the plot of the mosaic overlayed with the raw data, the mosaic should have each data point in 1 cell, however that is not the case - any help would be appreciated. However if you run data(tritest) x <- tritest$x y <- tritest$y vm <- voronoi.mosaic(x,y) plot(vm) par(new=T) plot(x,y,col='blue') it looks at it should. -zubin> > From: Prof Brian Ripley <ripley at stats.ox.ac.uk> > Date: 2006/07/19 Wed AM 03:15:51 EDT > To: Don MacQueen <macq at llnl.gov> > CC: zubin <binabina at bellsouth.net>, r-help at stat.math.ethz.ch > Subject: Re: [R] voronoi tessellations > > On Tue, 18 Jul 2006, Don MacQueen wrote: > > > I'll suggest going to the CRAN packages page and doing a search for "voronoi". > > The problem here is that `Voronoi tessellation' is a secondary name. The > concept has many names, including Dirichlet tessellation and Thiessen > polygons, and Dirichlet has priority over Voronoi. > > > Also, search for 'triangulation', since that is one of the uses of them. > > I know of packages deldir, tripack and perhaps geometry. > > > -Don > > > > At 11:46 PM -0400 7/18/06, zubin wrote: > > >Hello, looking to draw a voronoi tessellations in R - can anyone > > >recommend a package that has tackled this? > > > > > >some background: > > > > > >i have a economic data set and created a sammons projection, like to now > > >overlay a voronoi tessellation over the sammons 2-D solution for a slick > > >visual, and potentially color each tessellation element based on a metric. > > > > > >home.u <- unique(home1) > > >home.dist <- dist(home.u) > > >home.sam <- sammon(home.dist,k=2) > > >plot(home.sam$points) > > Wait a minute. If this is sammon() from MASS (uncredited), it is not a > projection, and there is no relevant concept of distance between points in > the mapped space apart from between the supplied points. > > I suggest Zubin reads carefully the reference whose support software he > appears to be using. (It would also have answered his question.) > > -- > Brian D. Ripley, ripley at stats.ox.ac.uk > Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ > University of Oxford, Tel: +44 1865 272861 (self) > 1 South Parks Road, +44 1865 272866 (PA) > Oxford OX1 3TG, UK Fax: +44 1865 272595 >
On 7/19/2006 4:21 PM, binabina at bellsouth.net wrote:> Okay, been working with tripack, seems the most mature package for this. Got it to work well with their test data set - data(tritest). When i tried random numbers to explore further, i am getting some results that don't reconcile. > > example run this: > > library(tripack) > y <- runif(100) > x <- runif(100) > vm <- voronoi.mosaic(x,y) > plot(vm) > par(new=T)Don't do that! That throws away the coordinate system that has already been established. Do it this way: library(tripack) y <- runif(100) x <- runif(100) vm <- voronoi.mosaic(x,y) plot(vm) points(x,y,col='blue') and if you want the axes, axis(1) axis(2) box() Duncan Murdoch> plot(x,y,col='blue') > > when you look at the plot of the mosaic overlayed with the raw data, the mosaic should have each data point in 1 cell, however that is not the case - any help would be appreciated. > > However if you run > > data(tritest) > x <- tritest$x > y <- tritest$y > vm <- voronoi.mosaic(x,y) > plot(vm) > par(new=T) > plot(x,y,col='blue') > > it looks at it should. > > -zubin > > >> From: Prof Brian Ripley <ripley at stats.ox.ac.uk> >> Date: 2006/07/19 Wed AM 03:15:51 EDT >> To: Don MacQueen <macq at llnl.gov> >> CC: zubin <binabina at bellsouth.net>, r-help at stat.math.ethz.ch >> Subject: Re: [R] voronoi tessellations >> >> On Tue, 18 Jul 2006, Don MacQueen wrote: >> >>> I'll suggest going to the CRAN packages page and doing a search for "voronoi". >> The problem here is that `Voronoi tessellation' is a secondary name. The >> concept has many names, including Dirichlet tessellation and Thiessen >> polygons, and Dirichlet has priority over Voronoi. >> >>> Also, search for 'triangulation', since that is one of the uses of them. >> I know of packages deldir, tripack and perhaps geometry. >> >>> -Don >>> >>> At 11:46 PM -0400 7/18/06, zubin wrote: >>>> Hello, looking to draw a voronoi tessellations in R - can anyone >>>> recommend a package that has tackled this? >>>> >>>> some background: >>>> >>>> i have a economic data set and created a sammons projection, like to now >>>> overlay a voronoi tessellation over the sammons 2-D solution for a slick >>>> visual, and potentially color each tessellation element based on a metric. >>>> >>>> home.u <- unique(home1) >>>> home.dist <- dist(home.u) >>>> home.sam <- sammon(home.dist,k=2) >>>> plot(home.sam$points) >> Wait a minute. If this is sammon() from MASS (uncredited), it is not a >> projection, and there is no relevant concept of distance between points in >> the mapped space apart from between the supplied points. >> >> I suggest Zubin reads carefully the reference whose support software he >> appears to be using. (It would also have answered his question.) >> >> -- >> Brian D. Ripley, ripley at stats.ox.ac.uk >> Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ >> University of Oxford, Tel: +44 1865 272861 (self) >> 1 South Parks Road, +44 1865 272866 (PA) >> Oxford OX1 3TG, UK Fax: +44 1865 272595 >> > > ______________________________________________ > R-help at stat.math.ethz.ch mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code.
On Wed, 19 Jul 2006, binabina at bellsouth.net wrote:> Okay, been working with tripack, seems the most mature package for this. > Got it to work well with their test data set - data(tritest). When i > tried random numbers to explore further, i am getting some results that > don't reconcile. > > example run this: > > library(tripack) > y <- runif(100) > x <- runif(100) > vm <- voronoi.mosaic(x,y) > plot(vm) > par(new=T) > plot(x,y,col='blue')plot() changes the axis scales. Use points(x,y) -thomas> when you look at the plot of the mosaic overlayed with the raw data, the > mosaic should have each data point in 1 cell, however that is not the > case - any help would be appreciated. > > However if you run > > data(tritest) > x <- tritest$x > y <- tritest$y > vm <- voronoi.mosaic(x,y) > plot(vm) > par(new=T) > plot(x,y,col='blue') > > it looks at it should. > > -zubin > > >> >> From: Prof Brian Ripley <ripley at stats.ox.ac.uk> >> Date: 2006/07/19 Wed AM 03:15:51 EDT >> To: Don MacQueen <macq at llnl.gov> >> CC: zubin <binabina at bellsouth.net>, r-help at stat.math.ethz.ch >> Subject: Re: [R] voronoi tessellations >> >> On Tue, 18 Jul 2006, Don MacQueen wrote: >> >>> I'll suggest going to the CRAN packages page and doing a search for "voronoi". >> >> The problem here is that `Voronoi tessellation' is a secondary name. The >> concept has many names, including Dirichlet tessellation and Thiessen >> polygons, and Dirichlet has priority over Voronoi. >> >>> Also, search for 'triangulation', since that is one of the uses of them. >> >> I know of packages deldir, tripack and perhaps geometry. >> >>> -Don >>> >>> At 11:46 PM -0400 7/18/06, zubin wrote: >>>> Hello, looking to draw a voronoi tessellations in R - can anyone >>>> recommend a package that has tackled this? >>>> >>>> some background: >>>> >>>> i have a economic data set and created a sammons projection, like to now >>>> overlay a voronoi tessellation over the sammons 2-D solution for a slick >>>> visual, and potentially color each tessellation element based on a metric. >>>> >>>> home.u <- unique(home1) >>>> home.dist <- dist(home.u) >>>> home.sam <- sammon(home.dist,k=2) >>>> plot(home.sam$points) >> >> Wait a minute. If this is sammon() from MASS (uncredited), it is not a >> projection, and there is no relevant concept of distance between points in >> the mapped space apart from between the supplied points. >> >> I suggest Zubin reads carefully the reference whose support software he >> appears to be using. (It would also have answered his question.) >> >> -- >> Brian D. Ripley, ripley at stats.ox.ac.uk >> Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ >> University of Oxford, Tel: +44 1865 272861 (self) >> 1 South Parks Road, +44 1865 272866 (PA) >> Oxford OX1 3TG, UK Fax: +44 1865 272595 >> > > ______________________________________________ > R-help at stat.math.ethz.ch mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. >Thomas Lumley Assoc. Professor, Biostatistics tlumley at u.washington.edu University of Washington, Seattle