The r-sig-geo list, https://stat.ethz.ch/mailman/listinfo/r-sig-geo
is often a better place to post such geographically related queries. Cheers, Bert Bert Gunter "The trouble with having an open mind is that people keep coming along and sticking things into it." -- Opus (aka Berkeley Breathed in his "Bloom County" comic strip ) On Mon, Mar 19, 2018 at 6:18 AM, Kenneth Dyson <kenn...@kidscodejeunesse.org > wrote: > I am having trouble getting data labels to display over the provinces in a > GADM map of Canada. > Specifically, I need the variable "Number" from the data set > "by_province", grouped by "region", to appear on the corresponding regions > of the map. > > The data set "by_province" looks like this: > long lat order hole piece region > group Number > -110.37074 60.00006 1 FALSE 1 Alberta > Alberta.1 132 > -110.36250 60.00006 2 FALSE 1 Alberta > Alberta.1 132 > -110.35103 60.00006 3 FALSE 1 Alberta > Alberta.1 132 > and the data set "tract" is the map data without the "Number" variable. > I looked into working this out from by researching the geom_map function > here: http://ggplot2.tidyverse.org/reference/geom_map.html > my code looks like this: > # get the raw map data > can_map <- getData('GADM', country = "CAN", level = 1) # download map > level with provinces > tract <- fortify(can_map, region = "NAME_1") # transforms data from > shapefiles into a dataframe that ggplot can understand, from > http://www.kevjohnson.org/making-maps-in-r/ > > # create subsets of the kcj data if needed, for example by year > kids_data_2017 <- subset(kids_data, year == 2017) # data for the year 2017 > kids_data_2018 <- subset(kids_data, year == 2018) # data for the year 2018 > > # extract the needed data > kids_province_data <- data.table::data.table(kids_ > data_2017$Province_Territory__c, kids_data_2017$Number_of_kids__c) > names(kids_province_data)[1] <- "Province" > names(kids_province_data)[2] <- "Number" > > # sum the data by province > kids_province_sums <- aggregate(.~Province, data = kids_province_data, sum) > > # join the data to the map > names(tract)[6] <- "region" > names(kids_province_sums)[1] <- "region" > by_province <- left_join(tract, kids_province_sums) > > # create the data map > kids_map <- ggplot(by_province, aes(map_id = region)) + > #plots the map in by_province separating by region > geom_map(aes(fill = Number), > #generates aestheticsa for the plot > map = tract, > #takes the data from tract > color = "#ffffff", > #makes the color of the borders between regions white > size = 0.15) + > #sets the thickness of the boarder lines > coord_map("polyconic") + #sets > the coordinates to polyconic (rounded lat and long) > scale_fill_gradient(name = "Children Reached", #sets > the gradient of the value scale: names the scale > low = grey_2, > #color of the low end > high = orange_1) + > #color of the high end > expand_limits(x = tract$long, > #ensure limits include all values for all plots > y = tract$lat) + > labs(x = NULL, #add > labels, no x title > y = NULL, > #no y title > title = "Number of Children Reached by Province", > #map title > subtitle = "2017") + > #map subtitle > geom_text(data = by_province, #add a > text layer > aes(long, > #aethetics for the text, x axis > lat, > #y axis > label = Number, > #the value to display > size=3)) + > #size of the text > theme(axis.ticks = element_blank(), #theme > of the graph, no axis ticks > axis.text = element_blank(), > #no axis text > panel.background = element_blank(), > #blank background > panel.border = element_blank()) > #blank border > > # save as png > ggsave(kids_map, file = "kids_map.png", width = 6, height = 4.5, type = > "cairo-png”) > I have asked this question on stack overflow, and was refered to this > answer: > > https://stackoverflow.com/questions/9441436/ggplot-centered-names-on-a-map > The solution there did not fix my problem, though it did get me closer. > The solution on that post is using a single vector of labels. > > My post on stackoverflow has images of my output: > https://stackoverflow.com/questions/49118323/labelling- > a-map-plotted-with-geom-map > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/ > posting-guide.html > and provide commented, minimal, self-contained, reproducible code. > [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
