 Dear R-siggers,

I'm trying to produce a bubble plot using the sp package. The plot is ok, but there are two issues I would like to improve. To see them, please reproduce the code below:

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require(sp)
require(rgdal)

# Read PR shapefile
download.file('https://dl.dropboxusercontent.com/u/27700634/PR.zip', 'PR.zip')
unzip('PR.zip')
pr <- readOGR('.', 'PR')

# Read plot data
dcoef <- read.csv('https://dl.dropboxusercontent.com/u/27700634/data.csv',sep=';', header=T)

coordinates(dcoef) <- c('Longitude','Latitude')

# Coerce the polygon outlines to a SpatialLines object 
spl <- list('sp.lines', as(pr, 'SpatialLines'))

# basic bubble plot
bubble(dcoef, 'pvalue', main = 'P-values', key.entries = seq(0.2, 1, by=0.2), sp.layout=spl)
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Here is the first issue: how can I "zoom out" the plot to show the entire shapefile contour, and not focus only on the dots domain?

Now, going ahead with the code:

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# More sophisticated plot
rv = list('sp.polygons', pr, fill = 'lightgrey') # 
arrow = list('SpatialPolygonsRescale', 
             layout.north.arrow(), 
             offset=c(-51, -24), 
             scale = 0.5, which = 2)

bubble(dcoef, 'pvalue',                   # data.frame and column to be plotted
       main = 'P-values',                 # title
       col='red',                         # color of bubbles
       key.entries = seq(0.2, 1, by=0.2), # legend
       scales=list(draw = TRUE),          # degrees in axes
       sp.layout=list(rv, arrow))         # include additional items
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Here are two issues: 
i) same as below: how can I show the entire shapefile contour, and not focus only on the dots domain?

ii) why does the north arrow insist in not appearing?

Thanks in advance for any suggestion.

Greetings,
--
Thiago V. dos Santos
PhD student
Land and Atmospheric Science
University of Minnesota
http://www.laas.umn.edu/CurrentStudents/MeettheStudents/ThiagodosSantos/index.htm
Phone: (612) 323 9898
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