I am working on a project https://github.com/AlanInTsukuba/jpucd that
involves
extracting shapefiles and property data from Japanese geojson files. When
reading with readOGR(ibarakipath1 , encoding="UTF-8", use_iconv=TRUE),
I find that the subsets of cannot be written with writeOGR without losing
text fields that are in Japanese text. I found the following workaround but
wonder if there is a better way to do this.
Environment: RGui, Windows10
# load ibaraki shapefiles, extract TX subset, write to geojson
library(jpucd)
shppath <- system.file("extdata",package="jpucd")
ibarakipath1 <-
paste(shppath,"JPGen2005CTgenlCY2000P08Ibaraki.geojson",sep="/")
#^ JPGen2005CTgenlCY2000P08Ibaraki.geojson is a UTF-8 encoded geojson file
#^ having Japanese names in property fields. To be able to
#^ read these fields, they need to be converted (to switch-jis?).
#^ The following command does this.
#^ This can also be done by use_iconv=FALSE and setting
#^ the encoding of the Japanese columns using Encoding(x) <- "UTF-8".
ibaraki <- readOGR(ibarakipath1 , encoding="UTF-8", use_iconv=FALSE) ##
use_iconv=TRUE
## loads so that the Japanese fields are readable but writeOGR doesn?t
write them.
head(ibaraki at data)
#^ Apply Encoding(x) <- ?UTF-8?
for (name in colnames(ibaraki at data[,sapply(ibaraki @data, is.character)])){
Encoding(ibaraki @data[[name]]) <- "UTF-8"}
#^ Get TX subset
tx2000 <- ibaraki[ibaraki at data$CITY_NAME=="????"|ibaraki at data$CITY_NAME=="
???"
|ibaraki at data$CITY_NAME=="???"|ibaraki at data$CITY_NAME=="????
",]
head(tx2000 at data)
#^ Write it.
dsn <- "TsukubaExpressCensusDistricts2000.geojson"
writeOGR(tx2000 , dsn,layer="TsukubaExpressCensusDistricts2000" ,
driver="GeoJSON", dataset_options = NULL,
layer_options=NULL, verbose = FALSE, check_exists=NULL,
overwrite_layer=FALSE, delete_dsn=FALSE, morphToESRI=NULL,
encoding="UTF-8")
Thank you.
Alan
https://alanintsukuba.github.io/