I just had a play with ggplot2 in R, with syntax like
geom_map(data=world, map=world
aes(x=long, y=lat, map_id=region),
color="white", fill="#7f7f7f", size=0.05, alpha=1/4)
That gives me the world map, is it possible to only get UK map as background map?
Many thanks
Peddie
You can also do something like:
library(ggplot2)
library(ggthemes)
library(raster)
library(rgeos)
gbr <- getData("GADM", country="GBR", level=0)
gbr <- gSimplify(gbr, 0.01)
gbr_map <- fortify(gbr)
gg <- ggplot()
gg <- gg + geom_map(map=gbr_map, data=gbr_map,
aes(x=long, y=lat, map_id=id),
fill="#7f7f7f")
gg <- gg + coord_map()
gg <- gg + theme_map()
gg
Once my ggalt package is in CRAN you can even use a decent projection.
Also check out ggplot2::borders()
library(ggplot2)
ggplot() +
borders(reg="UK", color="white", fill="#7f7f7f", alpha=1/4)
The result should be equal to the one from #eipi10.
library(maps)
library(ggplot2)
dat=map_data("world")
ggplot() +
geom_map(data=dat[dat$region=="UK",], map=dat[dat$region=="UK",],
aes(x=long, y=lat, map_id=region),
color="white", fill="#7f7f7f", size=0.05, alpha=1/4) +
coord_fixed()
The library ggmap works very well with ggplot2.
You could try this:
library(ggmap)
#Google API
register_google(key = "your_api_key")
map <- get_map(location = 'UK', zoom = 6)
ggmap(map)
and add geom as you like.
Related
I'm creating a cloropleth map of the U.S where each county is colored by the proportion of the 2012 votes for Obama. I'd like to vary the opacity of county overlays by the population (similar to what was done here). I've tried adding alpha = populationVariable to my geom_map aes, but without luck.
Here is my current code. Can anyone point me in the right direction?
gg <- ggplot()
gg <- gg + geom_map(data=mapC, map=mapC, aes(x=long, y=lat, map_id=id, group=group, fill=mapC$proportionObama))
gg = gg+ scale_fill_gradient2(limits= c(0,100), name="Proportion of Votes for Obama", low="#E5000A", high="#0012BF",mid="#720964", midpoint=50)
gg = gg + theme_map() +coord_equal()
gg <- gg + geom_path(data = mapS, aes(long,lat, group=group), colour="gray50", size=.25)
gg = gg + theme(legend.position="right")
gg
I think that alpha needs to be a variable that's mapped to be between 0 and 1. The ggplot documentation always shows a fractional value.
Hue Scale - http://docs.ggplot2.org/0.9.3.1/scale_hue.html
Color Fill Alpha - http://docs.ggplot2.org/current/aes_colour_fill_alpha.html
You don't have reproducible code, so here was a quick test that seemed to work.
library(data.table)
library(ggplot2)
tmp = data.table(
'x'=c(1,2,3),
'y'=c(1,2,3),
'z'=c(.1,.5,.8)
)
p = ggplot()
p = p + geom_point( data=tmp , aes(x=x,y=y,alpha=z))
print(p)
I'm trying to plot a continuous variable on space. I saw this example that gets the same result that I need:
library("MASS")
library("ggplot2")
library(reshape2)
DB<-melt(volcano)
ggplot(DB, aes(x=Var1, y=Var2, fill=value)) +geom_tile()
So I did with my data:
library(repmis)
url<-"https://www.dropbox.com/s/4m5qk32wjgrjq40/dato.RDATA"
source_data(url)
library(ggplot2)
ggplot(dato,aes(y=variable,x=y,fill=value))+geom_tile()
That's wonderful. But my "x" and "y" are kilometers distance (east and north) from a point in space. I transformed these in latitude and longitude. But now my plot doesn't work!
ggplot(dato,aes(y=lat,x=long,fill=value))+geom_tile()
I don't understand why. Anyway plotting my data like points the result is very similar:
ggplot(dato,aes(y=lat,x=long,fill=value))+geom_point()
ggplot(dato,aes(y=variable,x=y,fill=value))+geom_point()
You can cheat a bit and use geom_point with a square shape:
#devtools::install_github("sjmgarnier/viridis")
library(viridis)
library(ggplot2)
library(ggthemes)
library(scales)
library(grid)
gg <- ggplot(dato)
gg <- gg + geom_point(aes(x=long, y=lat, color=value), shape=15, size=5)
gg <- gg + coord_equal()
gg <- gg + scale_color_viridis(na.value="#FFFFFF00")
gg <- gg + theme_map()
gg <- gg + theme(legend.position="right")
gg
I did not project the lat/long pairs and just used coord_equal. You should use a proper projection for the region being mapped.
And, now you have me curious as to what those hot spots are around Milan :-)
gmap <- get_map(location=c(9.051062, 45.38804, 9.277473, 45.53438),
source="stamen", maptype="toner", crop=TRUE)
gg <- ggmap(gmap)
gg <- gg + geom_point(data=dato, aes(x=long, y=lat, color=value), shape=15, size=5, alpha=0.25)
gg <- gg + coord_map()
gg <- gg + scale_color_viridis(na.value="#FFFFFF00")
gg <- gg + theme_map()
gg <- gg + theme(legend.position="right")
gg
So, I have a dataset that has data for not only CONUS but also the island areas and Alaska. Now, I want to plot only the data for CONUS. I know I can subset it easily. But is there any easier way to that? Maybe an option in ggplot I don't know?
Here is the code:
ggplot() +
geom_polygon( data=usamap, aes(x=long, y=lat,group=group),colour="black", fill="white" )+
geom_point(data=df,aes(x=Longitude,y=Latitude))+
scale_colour_gradientn(name = "DL",colours = myPalette(10))+
xlab('Longitude')+
ylab('Latitude')+
coord_map(projection = "mercator")+
theme_bw()+
theme(legend.position = c(.93,.20),panel.grid.major = element_line(colour = "#808080"))+
ggsave("test.png",width=10, height=8,dpi=300)
Here is the dataset:
https://www.dropbox.com/s/k1z5uquhtc2b9nd/exported.csv?dl=0
You can do it and also use a decent projection at the same time:
library(ggplot2)
library(readr)
library(dplyr)
us <- map_data("state")
us <- fortify(us, region="region")
# for theme_map
devtools::source_gist("33baa3a79c5cfef0f6df")
# read your data and filter out points not in CONUS
read_csv("exported.csv") %>%
filter(Longitude>=-124.848974 & Longitude<=-66.885444,
Latitude>=24.396308 & Latitude<=49.384358) -> data
gg <- ggplot()
gg <- gg + geom_map(data=us, map=us,
aes(x=long, y=lat, map_id=region, group=group),
fill="#ffffff", color="#7f7f7f", size=0.25)
gg <- gg + geom_point(data=data,
aes(x=Longitude, y=Latitude),
color="#cb181d", size=1, alpha=1/10)
gg <- gg + coord_map("albers", lat0=39, lat1=45)
gg <- gg + theme_map()
gg
You have no aesthetic color mapping I can see, so your color scaling will have no impact. I used an alpha for overlapping/close points instead.
Looking at your reposted question, I think by far the best way is a simple subset. From this link, you can see the box around the continental USA is:
(-124.848974, 24.396308) - (-66.885444, 49.384358)
if you do a simple subset:
usamap<-usamap[usamap$Longitude > -124.848 &
usamap$Longitude < -66.886 &
usamap$Latitude > 24.3964 &
usamap$Latitude < 49.3844, ]
You will get your required points.
Since you said you'd be interested in a ggplot2 solution, you might consider modifying the arguments in coord_map(). For example:
coord_map(project = "globular",
xlim = c(-125, -66),
ylim = c(24, 50))
Of course, the "mercator" argument works, too!
I'm trying to plot a US map where each state is shaded by the count that it has. I've gotten the shading to work just fine. The problem I'm running into, however, is that the polygons look very jagged (I'm assuming something happened when I tried to merge the map_data('state') with my data frame of counts per state). My data frame before merging has 49 rows (Nevada was missing data in my set), and after merging has many more rows (expected for the long/lat items for the states) but the data appears to be copied correctly for each lat/long pair, so I'm unsure why the poly's are so jagged.
Code:
ggplot() +
geom_polygon(data=try1, aes(x=long, y=lat, group = group, fill= COUNT)) +
scale_fill_continuous(low='thistle2', high='darkred', guide='colorbar') +
theme_bw() + labs(fill="State Map Try Title1", title='Title2', x='', y='') +
scale_y_continuous(breaks=c()) +
scale_x_continuous(breaks=c()) +
theme(panel.border = element_blank())
Any help would be greatly appreciated (and obviously, if there is a better way to do it, I'm open to suggestions!).
You don't need to do the merge. You can use geom_map and keep the data separate from the shapes. Here's an example using the built-in USArrests data (reformatted with dplyr):
library(ggplot2)
library(dplyr)
us <- map_data("state")
arr <- USArrests %>%
add_rownames("region") %>%
mutate(region=tolower(region))
gg <- ggplot()
gg <- gg + geom_map(data=us, map=us,
aes(x=long, y=lat, map_id=region),
fill="#ffffff", color="#ffffff", size=0.15)
gg <- gg + geom_map(data=arr, map=us,
aes(fill=Murder, map_id=region),
color="#ffffff", size=0.15)
gg <- gg + scale_fill_continuous(low='thistle2', high='darkred',
guide='colorbar')
gg <- gg + labs(x=NULL, y=NULL)
gg <- gg + coord_map("albers", lat0 = 39, lat1 = 45)
gg <- gg + theme(panel.border = element_blank())
gg <- gg + theme(panel.background = element_blank())
gg <- gg + theme(axis.ticks = element_blank())
gg <- gg + theme(axis.text = element_blank())
gg
I encountered a similar problem when using ggplot2. As an alternative to #hrbrmstr 's solution, I found reloading the ggplot2 package (as well as rgdal/`maptools') resolved the issue for me.
I am new here and I am trying to plot points on a map of a coastal region - therefore I would like to show a coastline and colour just one country, surrounded by adjoining countries.
My code is
library(maps)
library(mapdata)
map("worldHires", xlim=c(-90,-70), ylim=c(-20,-2), # Re-defines the latitude and longitude range
col = "gray", fill=TRUE)
However I would like to colour in just Peru. I have so far managed to do this:
map('worldHires', 'Peru', col = "grey90", fill=TRUE, xlim=c(-90,-70), ylim=c(-20,-2))
but this doesn't show adjoining countries, and I would really like to show all adjoining countries and just colour Peru.
I have seen advice in another thread using the simple map tool - but there is slightly less detail (see below)
library(maptools)
data(wrld_simpl)
plot(wrld_simpl,
col = c(gray(.80), "red")[grepl("Peru", wrld_simpl#data$NAME) + 1],
xlim=c(-90,-70), ylim=c(-20,-2))
Does anyone know how to do it using worldhires? It's probably really simple and I just haven't worked it out.
The trick is to use map() to extract the Peru boundaries, then overplotting the Peru fill on a worlmap outline.
library(maps)
library(mapdata)
peru <- map("worldHires", regions="Peru", plot=FALSE, fill=TRUE)
map("worldHires", xlim=c(-100,-30), ylim=c(-30,10))
map(peru, col="red", fill=TRUE, add=TRUE)
A Hadleyverse version via ggplot:
library(maps)
library(mapdata)
library(ggplot2)
coast_map <- fortify(map("worldHires", fill=TRUE, plot=FALSE))
gg <- ggplot()
gg <- gg + geom_map(data=coast_map, map=coast_map,
aes(x=long, y=lat, map_id=region),
fill="white", color="black")
gg <- gg + geom_map(data=data.frame(region="Peru"), map=coast_map,
aes(map_id=region), fill="steelblue")
gg <- gg + xlim(-90,-70) + ylim(-20,-2)
gg <- gg + coord_map()
gg <- gg + theme_bw()
gg