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#Gets PCT Values for the road segments
#Functions
find.pct.lines <- function(i){
#message(i)
pct_sub <- pct.all[i,]
pct_id <- pct_sub$ID[1]
grid_ids <- grid_pct2grid[[i]]
osm_ids <- unique(unlist(grid_grid2osm[grid_ids]))
osm_sub <- osm[osm_ids,]
res <- roadsOnLine(roads = osm_sub, line2check = pct_sub$geometry, tolerance = 4)
return(res)
}
#get pct row numbers for a given osm row number
getpctids <- function(y){
return(seq_along(pct2osm)[sapply(seq_along(pct2osm),function(x){y %in% pct2osm[[x]]})])
}
#get pct values for a given osm row number
getpctvalues <- function(i){
pct.sub <- pct.all[osm2pct[[i]],]
count <- data.frame(id = i,
pct.census = sum(pct.sub$pct.census),
pct.gov = sum(pct.sub$pct.gov),
pct.gen = sum(pct.sub$pct.gen),
pct.dutch = sum(pct.sub$pct.dutch) ,
pct.ebike = sum(pct.sub$pct.ebike),
pct.total = sum(pct.sub$pct.total))
}
#List folders
regions <- regions.todo
for(b in 1:length(regions)){
if(file.exists(paste0("../cyipt-bigdata/osm-prep/",regions[b],"/osm-lines.Rds"))){
#Get file
osm <- readRDS(paste0("../cyipt-bigdata/osm-prep/",regions[b],"/osm-lines.Rds"))
#Check if PCT values exist in the file
if(all(c("pct.census","pct.gov","pct.gen","pct.dutch","pct.ebike","pct.total") %in% names(osm)) & skip){
message(paste0("PCT values already calcualted for ",regions[b]," so skipping"))
}else{
message(paste0("Getting PCT values for ",regions[b]," at ",Sys.time()))
#If overwriting remove old data
col.to.keep <- names(osm)[!names(osm) %in% c("pct.census","pct.gov","pct.gen","pct.dutch","pct.ebike","pct.total")]
osm <- osm[,col.to.keep]
rm(col.to.keep)
#Get bounding box
ext <- st_bbox(osm)
ext <- st_sfc(st_polygon(list(rbind(c(ext[1],ext[2]),c(ext[3],ext[2]),c(ext[3],ext[4]),c(ext[1],ext[4]),c(c(ext[1],ext[2]))))) )
pol <- data.frame(id = 1, geometry = NA)
st_geometry(pol) <- ext
rm(ext)
#Get pct data and subset to bounding box
pct.all <- readRDS("../cyipt-securedata/pct-routes-all.Rds")
st_crs(pol) <- st_crs(pct.all) #For some reason the CRS are fractionally different
pct.all <- pct.all[pol,]
pct.all <- st_transform(pct.all, st_crs(osm)) #transfor so that crs are idetical
#Futher subset using the region boundary
bounds <- readRDS("../cyipt-bigdata/boundaries/TTWA/TTWA_England.Rds")
bounds <- bounds[bounds$ttwa11nm == regions[b],]
bounds <- st_transform(bounds, st_crs(osm))
nrow(pct.all)
pct.all <- pct.all[bounds,]
nrow(pct.all)
#add total column
pct.all$total <- pct.all$pct.census + pct.all$onfoot + pct.all$workathome + pct.all$underground + pct.all$train + pct.all$bus + pct.all$taxi + pct.all$motorcycle + pct.all$carorvan + pct.all$passenger + pct.all$other
# Check if pct lines are completly inside the region
inside <- st_contains_properly(bounds,pct.all, sparse = FALSE)
inside <- t(inside)
pct.all$insideRegion <- inside[,1]
rm(inside)
if(verbose){message(paste0("Warning: ",sum(pct.all$insideRegion == FALSE)," of ",length(pct.all$ID)," (",round(sum(pct.all$insideRegion == FALSE)/length(pct.all$ID)*100,1)," %)"," of PCT lines cross the region boundary"))}
#save selection for later use
saveRDS(pct.all,paste0("../cyipt-securedata/pct-regions/",regions[b],".Rds"))
#remove the values we no longer need
pct.all <- pct.all[,c("ID","pct.census","pct.gov","pct.gen","pct.dutch","pct.ebike","all_16p")]
names(pct.all) <- c("ID","pct.census","pct.gov","pct.gen","pct.dutch","pct.ebike","pct.total","geometry")
#Performacne Tweak, Preallocate object to a grid to reduce processing time
grid <- st_make_grid(osm, n = c(500,500), what = "polygons")
grid_pct2grid <- st_intersects(pct.all, grid) # Which grids is each pct line in?
grid_grid2osm <- st_intersects(grid, osm)# for each grid which osm lines cross it
# Make a PCT to OSM Lookup Table
##########################################################
#Parallel
m = 1
n = nrow(pct.all)
start <- Sys.time()
fun <- function(cl){
parLapply(cl, m:n,find.pct.lines)
}
cl <- makeCluster(ncores) #make clusert and set number of cores
clusterExport(cl=cl, varlist=c("grid_pct2grid", "pct.all","grid_grid2osm","osm"))
clusterExport(cl=cl, c('find.pct.lines') )
clusterEvalQ(cl, {library(sf); source("R/functions.R")})
pct2osm <- fun(cl)
stopCluster(cl)
end <- Sys.time()
if(verbose){message(paste0("Did ",n," lines in ",round(difftime(end,start,units = "secs"),2)," seconds, in parallel mode at ",Sys.time()))}
##########################################################
saveRDS(pct2osm,paste0("../cyipt-bigdata/osm-prep/",regions[b],"/pct2osm.Rds"))
# Convert A PCT to OSM lookup to an OSM to PCT lookup
# We do this in a backwards way becuase we need the PCT to OSM one later
##########################################################
#Parallel
m = 1
n = nrow(osm)
start <- Sys.time()
fun <- function(cl){
parLapply(cl, m:n,getpctids)
}
cl <- makeCluster(ncores) #make clusert and set number of cores
clusterExport(cl=cl, varlist=c("pct2osm"))
clusterExport(cl=cl, c('getpctids') )
osm2pct <- fun(cl)
stopCluster(cl)
end <- Sys.time()
if(verbose){message(paste0("Got ",n," lines of PCT ids in ",round(difftime(end,start,units = "secs"),2)," seconds, in parallel mode at ",Sys.time()))}
##########################################################
saveRDS(osm2pct,paste0("../cyipt-bigdata/osm-prep/",regions[b],"/osm2pct.Rds"))
#Now for each osm line get the pct values
##########################################################
#Parallel
m = 1
n = nrow(osm)
start <- Sys.time()
fun <- function(cl){
parLapply(cl, m:n,getpctvalues)
}
cl <- makeCluster(ncores) #make clusert and set number of cores
clusterExport(cl=cl, varlist=c("osm2pct","pct.all"))
clusterExport(cl=cl, c('getpctvalues') )
pct_vals <- fun(cl)
stopCluster(cl)
end <- Sys.time()
if(verbose){message(paste0("Got ",n," lines of PCT values in ",round(difftime(end,start,units = "secs"),2)," seconds, in parallel mode at ",Sys.time()))}
##########################################################
pct_vals <- bind_rows(pct_vals)
osm <- left_join(osm, pct_vals, by = c("id" = "id"))
rm(cl,end,n,m)
#Save results
if(overwrite){
saveRDS(osm,paste0("../cyipt-bigdata/osm-prep/",regions[b],"/osm-lines.Rds"))
}else{
saveRDS(osm,paste0("../cyipt-bigdata/osm-prep/",regions[b],"/osm-lines-pct.Rds"))
}
rm(osm,pct.all,pct_vals,osm2pct,pct2osm,grid,grid_grid2osm,grid_pct2grid, pol, bounds)
}
}else{
message(paste0("Input File Missing for ",regions[b]," at ",Sys.time()))
}
}
rm(b,regions)
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