R Under development (unstable) (2013-06-11 r62941) -- "Unsuffered Consequences"
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> 
> # Read SVG
> library(XML)
> svg <- xmlParse("Multilingualism.svg")
> 
> # Get all polygons
> polys <- getNodeSet(svg, "//svg:polygon",
+                     namespaces=c(svg="http://www.w3.org/2000/svg"))
> 
> # Function to test polygon for inclusion
> keep <- function(p) {
+     coords <- matrix(as.numeric(strsplit(xmlAttrs(p)["points"],
+                                          " |,")[[1]]), nrow=2)
+     all(coords[1,] > 300 & coords[1,] < 310 &
+         coords[2,] > 430 & coords[2,] < 440)
+ }
> 
> retain <- sapply(polys, keep)
> 
> # Function to scale polygons we want to keep
> transform <- function(x) {
+     x <- sweep(x, 1, c(300, 400))
+     x <- x*16
+     x <- sweep(x, 1, c(90, 60), "+")
+     x
+ }
> scale <- function(p) {
+     attrs <- xmlAttrs(p)
+     coords <- matrix(as.numeric(strsplit(attrs["points"],
+                                          " |,")[[1]]), nrow=2)
+     newcoords <- transform(coords)
+     attrs["points"] <- paste(apply(round(newcoords, 2), 2,
+                                    paste, collapse=","),
+                              collapse=" ")
+     xmlAttrs(p) <- attrs
+ }
> 
> invisible(lapply(polys[retain], scale))
> 
> # Function to remove polygon parent <g> from its parent
> remove <- function(p) {
+     removeChildren(xmlParent(xmlParent(p)), xmlParent(p))
+ }
> 
> invisible(lapply(polys[!retain], remove))
> 
> saveXML(svg, "Multilingualism-Auckland.svg")
[1] "Multilingualism-Auckland.svg"
> 
> proc.time()
   user  system elapsed 
157.089   0.080 157.601