问将栅格转换为R中的csv

EN

as.data.frame( rasterToPoints(species) )

Error in as.data.frame.default(x[[i]], optional = TRUE) : 
cannot coerce class "structure("RasterLayer", package = "raster")"   to a data.frame

#start loop
file.names <- dir(path, pattern=".csv")

for(i in 1:length(file.names)){
  file<- read.csv(file.name[i], header = TRUE, stringsAsFactors=FALSE)

#subsetting each file and renaming column header names
sub.file<-subset(file, select = c('Matched.Scientific.Name',  'Vernacular.Name...matched', 'Latitude...processed', 'Longitude...processed'))
names(sub.file) <- c('species', 'name', 'Lat','Lon')

#turn into a SpatialPointsDataFrame 
coordinates(sub.file) <- ~ Lon + Lat 
proj4string(sub.file) <- '+init=EPSG:4326'
plot(sub.file, axes=TRUE)

#converting to BNG
sub.file.BNG <- spTransform(sub.file, '+init=EPSG:27700')
plot(sub.file.BNG, axes=TRUE)

#creating template raster
template <- raster(xmn=400000, xmx=600000, ymn=200000, ymx=800000,  res=25000, crs='+init=EPSG:27700')

#point data > presence grid
species <- rasterize(sub.file.BNG, template, field=1)
plot(species)

# UK wide
template <- raster(xmn=-200000, xmx=700000, ymn=0, ymx=1250000, res=25000, crs='+init=EPSG:27700')

# use that to turn species point data into a presence grid
species <- rasterize(sub.file, template, field=1)
plot(species)

#converting a raster>dataframe>csv?????
as.data.frame( rasterToPoints(species) )
}