I have data for 357 grids for India. with some value at every grid. I want to plot it in R. I use following lines
library(maps)
library(ggplot2)
data <- read.csv("foo.csv")
ind <- map(database = "world", regions = "india", exact = FALSE, boundary = T)
india <- map_data(ind , region = "india", exact = F)
(ggplot(aes(x=x, y=y, fill=z), data=data) + geom_tile()) + geom_polygon(data=india, aes(x=long, y=lat, group=group), colour="black", fill="red", alpha=0)
But I got a very bad map.
How can I improve this image? I have seen some good ways at
R Plot Filled Longitude-Latitude Grid Cells on Map
But unfortunately these methods did not work in my case. Any will be highly appreciated.