R trying to find latitude/longitude data for cities in europe and getting geocode error messege

You have to geocode just the cities column (it's a little confusing that you have a data frame called cities, and within it a column called cities). When in doubt, try breaking things down into smaller chunks.

For example, try them one at a time ...

cities <- c("ARNHEM","ATHENS","BAAR","CAMBRIDGESHIRE")library(ggmap)geocode(cities[1])##       lon     lat## 1 5.89873 51.9851geocode(cities[2])## just checking ...geocode("ATHENS GEORGIA")##         lon   lat## 1 -83.38333 33.95

Now try the vector all at once:

geocode(cities)##          lon      lat## 1  5.8987296 51.98510## 2 23.7293097 37.98372## 3  8.5286332 47.19585## 4  0.0965375 52.27619

Now try with a data frame:

mydat <- read.csv(textConnection("   cities,Freq,lon,lat   ARNHEM,1.00,NA,NA   ATHENS,3.25,NA,NA   BAAR,1.00,NA,NA   BAD VILBEL,1.00,NA,NA   BILTHOVEN,1.00,NA,NA   BOGUS_PLACE,2,NA,NA"))geocodes <- geocode(as.character(mydat$cities))mydat <- data.frame(mydat[,1:2],geocodes)##               cities Freq        lon      lat## 1             ARNHEM 1.00   5.898730 51.98510## 2             ATHENS 3.25  23.729310 37.98372## 3               BAAR 1.00   8.528633 47.19585## 4         BAD VILBEL 1.00   8.739480 50.18234## 5          BILTHOVEN 1.00   5.210381 52.13653## 6        BOGUS_PLACE 2.00 -92.201158 44.49091

I don't know what the result for BOGUS_PLACE means ...!!

I have just found that this error message:

Error: is.character(location) is not TRUE

can be due to the address being encoded as a number, not a character. This can happen when you select from a data frame for instance, which was my case.

Do:

typeof(address)

and if it turns out to be numeric, change it to char

a2 <- as.character(address)geocode(a2)

Here is an alternative way you could handle this.

# METHOD 1: Using geocode() from {ggmap}library(ggmap)adr <- adr <- "Agra, New Delhi"  # define addressgeocode(adr)  # get the latitude and longitude# Information from URL : http://maps.googleapis.com/maps/api/geocode/json?address=Agra,+New+Delhi&sensor=false#     lon      lat1 77.3126 28.54637# METHOD 2: CODE TO GET THE LATITUDE AND LONGITUDE OF A STREET ADDRESS WITH GOOGLE APIaddr <- '6th Main Rd, New Thippasandra, Bengaluru, Karnataka'  # set your address hereurl = paste('http://maps.google.com/maps/api/geocode/xml?address=', addr,'&sensor=false',sep='')  # construct the URLdoc = xmlTreeParse(url) root = xmlRoot(doc) lat = xmlValue(root[['result']][['geometry']][['location']][['lat']]) long = xmlValue(root[['result']][['geometry']][['location']][['lng']]) lat[1] "12.9725020"long[1] "77.6510688"