我正在尝试使用气候数据运算符（cdo）在RStudio中计算ETCCDI暖期持续时间指数（wsdi）。我使用以下脚本，并使用KNMI网页中的可用值检查了结果。结果与KNMI中提供的结果不匹配。 clippedtasmax_2100.nc文件中的所有clippedtasmax_1981.nc文件（单位在dC中）都在input_folder中。您能告诉我此脚本有什么问题吗？
library(raster)
library(ncdf4)
startyear <- 1981
endyear <- 2100
for (i in startyear:endyear)
{
file_tmax <- paste(input_folder,"\\clippedtasmax_ ",i,".nc",sep="")
command <- paste("cdo timmin ",file_tmax," ",workdir,"tmax_min.nc",sep="")
system(command)
command <- paste("cdo timmax ",file_tmax," ",workdir,"tmax_max.nc",sep="")
system(command)
command <- paste("cdo timpctl,90 ",file_tmax," ",workdir,"tmax_min.nc ",workdir,"tmax_max.nc ",workdir,"temp_tmax_90.nc",sep="")
system(command)
command <- paste("cdo -add ",workdir,"temp_tmax_90.nc -sub ",file_tmax," ",file_tmax," ",workdir,"temp_tmax_90_timesteps.nc",sep = "")
system(command)
command <- paste("cdo eca_hwfi ",file_tmax," ",workdir,"temp_tmax_90_timesteps.nc ",outdir,"\\Warmspell_",i,".nc",sep = "")
system(command)
}
然后，我对输出的“ Warmspell_i.nc”文件进行了重新采样。
rm(list=ls())
library(raster)
#create new reference raster
referenceraster<-raster(xmn=80, xmx=90, ymn=25, ymx=30,
crs=CRS('+proj=longlat +datum=WGS84'))
res(referenceraster)<-2.5
referenceraster
#files to be resampled
wsdi<-"X:\\outdir\\warmspell_1981.nc"
wsdi<-raster(wsdi)
wsdi
resample_raster<-resample(wsdi, referenceraster, method="bilinear", nas.rm=TRUE)
values(resample_raster)
extent<-extent(80, 90, 25, 30)
e <- extract(resample_raster, extent, weights=TRUE, fun=mean)
e
谢谢。