Convert map data to data frame using fortify {ggplot2} for spatial objects in R

问题:

I use to be able to run this script without any problem, but now the fortify {ggplot2} command gives me an error message. Any hint of what might be the problem would be great! I used the fortify command to be able to geom_map the shapefile using ggplot2.

Below is my script and link for downloading the data.

####################################################### ####################################################### rm(list = ls(all = TRUE))#clear workspace getwd() #upload packages library(maps) library(mapdata) library(gridExtra) library(rgdal) library(rgeos) library(ggplot2) library(sp) library(maptools) gpclibPermit()  #setwd(".../FAO") FAO data are major fishing area divisions > FAO names(FAO);dim(FAO) [1] "zone" [1] 19  1 > str(FAO,max.level=2) Formal class 'SpatialPolygonsDataFrame' [package "sp"] with 5 slots   ..@ data       :'data.frame': 19 obs. of  1 variable:   ..@ polygons   :List of 19   ..@ plotOrder  : int [1:19] 18 2 17 4 12 3 13 11 5 6 ...   ..@ bbox       : num [1:2, 1:2] -180 -85.5 180 90   .. ..- attr(*, "dimnames")=List of 2   ..@ proj4string:Formal class 'CRS' [package "sp"] with 1 slots > plot(FAO) 

FAO@data$id = rownames(FAO@data) FAO.df  FAO_fort 

Here's a link to download the data FAO data. Thank you!

回答1:

I got it to work in ggplot2 and here is how I did it with the version and session info at the bottom.

The Map in ggplot2

The Code

rm(list = ls(all = TRUE)) #clear workspace  library(maptools) library(gpclib) library(ggplot2)  shape

The Session

> sessionInfo() R version 2.15.0 (2012-03-30) Platform: x86_64-apple-darwin9.8.0/x86_64 (64-bit)  locale:     [1] C/en_US.UTF-8/C/C/C/C  attached base packages:     [1] grid      stats     graphics  grDevices utils     [6] datasets  methods   base       other attached packages:     [1] mapproj_1.1-8.3 gpclib_1.5-1    maptools_0.8-14 [4] lattice_0.20-6  foreign_0.8-49  rgeos_0.2-5     [7] stringr_0.6     sp_0.9-99       gridExtra_0.9   [10] mapdata_2.2-1   ggplot2_0.9.0   maps_2.2-5       loaded via a namespace (and not attached):     [1] MASS_7.3-17        RColorBrewer_1.0-5 colorspace_1.1-1   [4] dichromat_1.2-4    digest_0.5.2       memoise_0.1        [7] munsell_0.3        plyr_1.7.1         proto_0.3-9.2      [10] reshape2_1.2.1     scales_0.2.0       tools_2.15.0 

回答2:

Fortify is likely to be deprecated. A new alternative is broom (see documentation here). It is very simply to use:

# Load shapefile FAO 

Unfortunately, the file you uploaded is not there anymore, so I cannot demonstrate the command for your example.

文章来源: Convert map data to data frame using fortify {ggplot2} for spatial objects in R