使用从159个独立NCDF4文件中提取的变量编写单个NCDF4文件

Question

我有159个Ncdf4文件，每个文件有56个集合。我想从159个输入文件中的每个文件中提取出系综组1。然后生成一个单独的NCDF4文件，将所有集合1放在一个文件中。我的代码如下。我的问题是，只有159的最后一个文件的数据被写入输出文件。我想我错过了一个嵌套循环，但不确定，我的尝试失败了。

rm(list=ls())
library(ncdf.tools)
library(ncdf4)
library(ncdf4.helpers)
library(RNetCDF)

setwd("D:/Rwork/Project")   # set working folder

#####Write NCDF4 files#############################################
dir("D:/Rwork/Project/Test")->xlab # This is the directory where the file for analysising are
filelist <- paste("Test/",dir("Test"),sep="")


N <- length(filelist)     # Loop over the individual files
for(j in 1:N){

File<-nc_open(filelist[j])
print(filelist[j])  
Temperature<-ncvar_get(File,"t2m")
Lat<-ncvar_get(File, "lat")
Lon<-ncvar_get(File,"lon")
Time<-ncvar_get(File,"time")
EnsambleNo.<-ncvar_get(File,"ensemble_member")
Temperature
Ensamble1<-Temperature[,,1,] #The Ensamble wanted, 1 to 56
Ensamble1<-round(Ensamble1,digits = 0)

tunits<-"hours since 1800-01-01 00:00:00"

#Define dimensions
##################################################################
londim<-ncdim_def("Lon","degrees_east",as.double(Lon))
latdim<-ncdim_def("Lat", "degrees_north",as.double(Lat))
timedim<-ncdim_def("Time",tunits,as.double(Time))

#Define variables
##################################################################
fillvalue<-1e32

dlname<-"tm2"

tmp_def<-ncvar_def("Ensamble1","deg_K", list(londim,latdim,timedim),fillvalue,dlname,prec =       "double")

ncfname<-("D:/Rwork/Project/TrialEnsamble/TrialEnsamble.nc")
ncout<-nc_create(ncfname,list(tmp_def),force_v4=T)

ncvar_put(ncout,tmp_def,Ensamble1,start=NA,count = NA )# Think I need a  nested loop here


ncatt_put(ncout,"Lon","axis","X")
ncatt_put(ncout, "Lat", "axis", "Y")
ncatt_put(ncout, "Time","axis", "T")

title<-c( 1:2 )
names(title)<-c("Ian","Gillespie")
title<-as.data.frame(title)

ncatt_put(ncout,0,"Make_NCDF4_File",1, prec="int")
ncatt_put(ncout,0,"Maynooth_University",1,prec="short")
ncatt_put(ncout,0,"AR000087828",1, prec="short")
ncatt_put(ncout,0,"mickymouse",1, prec="short")

history <- paste("P.J. Bartlein", date(), sep=", ")
ncatt_put(ncout,0,"description","this is the script to write NCDF4 files")

#Close file and write date to disk
 ##########################################################
nc_close(ncout)

}

Answer 1

我发现，最好准备一个四维的空数组，其中前三个维度的大小相同，并将维度命名为从for循环生成的具有额外第四维的数组。第四个维度用于保存每次迭代的结果dir("D:/Rwork/Project/Test")->xlab #这是用于分析的文件列表<- paste("Test/"，dir("Test")，sep="")所在的目录

output <- array(, dim=c(192,94,12,160))# need to change this to   length(Lat), etc

N <- length(filelist)     # Loop over the individual files
for(j in 1:N){

  File<-nc_open(filelist[j])
  print(filelist[j])  
  Temperature<-ncvar_get(File,"t2m")
  Lat<-ncvar_get(File, "lat")
  Lon<-ncvar_get(File,"lon")
  Time<-ncvar_get(File,"time")
  Year<-c(1851:2010)
  EnsambleNo.<-ncvar_get(File,"ensemble_member")
  Temperature
  Lat<-round(Lat,digits = 2)
  Lon<-round(Lon,digits = 2)
  Ensamble1<-Temperature[,,1,] #The Ensamble wanted, 1 to 56
  Ensamble1<-round(Ensamble1,digits = 1)
  dimnames(Ensamble1)<-list(Lon,Lat,Time)
  dimnames(output) <- list(Lon,Lat,Time,Year)
  }

  print(Ensamble1)