if (0){
#require(PBSmapping);
shpFile <- paste(system.file(package = "RgoogleMaps"), "/shapes/bg11_d00.shp", sep = "")
#shpFile <- system.file('bg11_d00.shp', package = "RgoogleMaps");
shp=PBSmapping::importShapefile(shpFile,projection="LL");
bb <- qbbox(lat = shp[,"Y"], lon = shp[,"X"]);
MyMap <- GetMap.bbox(bb$lonR, bb$latR, destfile = "DC.png");
PlotPolysOnStaticMap(MyMap, shp, lwd=.5, col = rgb(0.25,0.25,0.25,0.025), add = F);
#Try an open street map:
mapOSM <- GetMap.bbox(bb$lonR, bb$latR, destfile = "DC.png", type="osm");
PlotPolysOnStaticMap(mapOSM, shp, lwd=.5, col = rgb(0.75,0.25,0.25,0.15), add = F);
#North Carolina SIDS data set:
shpFile <- system.file("shapes/sids.shp", package="rgooglemaps");
shp=PBSmapping::importShapefile(shpFile,projection="LL");
bb <- qbbox(lat = shp[,"Y"], lon = shp[,"X"]);
MyMap <- GetMap.bbox(bb$lonR, bb$latR, destfile = "SIDS.png");
#compute regularized SID rate
sid <- 100*attr(shp, "PolyData")$SID74/(attr(shp, "PolyData")$BIR74+500)
b <- as.integer(cut(sid, quantile(sid, seq(0,1,length=8)) ));
b[is.na(b)] <- 1;
opal <- col2rgb(grey.colors(7), alpha=TRUE)/255; opal["alpha",] <- 0.2;
shp[,"col"] <- rgb(0.1,0.1,0.1,0.2);
for (i in 1:length(b))
shp[shp[,"PID"] == i,"col"] <- rgb(opal[1,b[i]],opal[2,b[i]],opal[3,b[i]],opal[4,b[i]]);
PlotPolysOnStaticMap(MyMap, shp, lwd=.5, col = shp[,"col"], add = F);
#or choose an aspect ratio that corresponds better to North Carolina's elongated shape:
MyMap <- GetMap.bbox(bb$lonR, bb$latR, destfile = "SIDS.png", size = c(640, 320), zoom = 7);
PlotPolysOnStaticMap(MyMap, shp, lwd=.5, col = shp[,"col"], add = F);
}
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