r-grid

Several functions in R's base graphical system, including rect() and polygon() , support cross-hatching via their angle= and density= arguments: x = c(0, 0.5, 1, 0.5) y = c(0.5, 1, 0.5, 0) par(mar=c(0,0,0,0)) plot.new() polygon(x, y, angle=45, density=10) How might I apply similar cross-hatching to a polygon drawn by the grid graphical system's grid.polygon() function: library(grid) grid.newpage() grid.polygon(x,y) I've looked in the documentation for ?grid.polygon and ?gpar , and have skimmed through Paul Murrel's book on R graphics, and have so far come up empty. Am I missing something

Is there a way to individually change the color of the text of a cell when using tableGrob and ggplot2? For instance in the code below it'd be great if the cell with 1 could be blue and the cell with 2 could be red, with 3:8 all black. library(ggplot2) library(grid) mytable = as.table(matrix(c("1","2","3","4","5","6","7","8"),ncol=2,byrow=TRUE)) mytable = tableGrob(mytable,gpar.coretext = gpar(col = "black", cex = 1)) mydf = data.frame(x = 1:10,y = 1:10) ggplot( mydf, aes(x, y)) + annotation_custom(mytable) Much to my disappointment, this does not seem to be easy. The tableGrob function calls

I am trying to make a map with two legends denoting shape and colour ("Type" and "Org" in the example below), and have the legends inset. I can place the legends, but I would like them to be left justified so that their left edges line up. I can't make them anything other than centred with respect to each other: require(ggplot2) require(ggmap) require(grid) require(mapproj) data <- data.frame(Org=rep(c("ABCDEFG","HIJKLMNOP","QRSTUVWX"),4) , Type=rep(c("Y","Z"),6), Lat=runif(12,48,54.5) , Long=runif(12,-133.5,-122.5)) osmMap <- get_map(location=c(-134,47.5,-122,55), source = 'osm') points <-

I've got a ggplot where I'm mapping factors to both fill and alpha, like this: set.seed(47) the_data <- data.frame(value = rpois(6, lambda=20), cat1 = rep(c("A", "B"), each = 3), cat2 = rep(c("X", "Y", "Z"), 2)) ggplot(the_data, aes(y = value, x = cat2, alpha = cat1, fill = cat2)) + geom_bar(stat = "identity", position = "dodge") + scale_alpha_discrete(range = c(0.5, 1)) + theme_bw() The people I'm producing it for don't find the legend for alpha very clear. I think a good alternative would be something like this (which I hacked together in base graphics): I know I can't generate a legend like

as a new ggplot2 user, I am a bit lost with the amount of possibilities, and struggle to find on the net a simple answer to what I consider a simple problem. I would like to display multiple plots from ggplot2 on a same sheet, BUT knowing that these plots come from a for loop. Following example does not compile, it is only to illustrate : for(i in c(1:n)){ for(j in c(1:m)){ .......... # some data production p <- ggplot(df.all) + geom_bar(aes_string(x=class.names[i],fill=var.names[j]) }} Here, p is overwritten, but I would like to have instead a matrix or a list in which I can put all the p as