我正在尝试使用R包ncdf创建一个多维NetCDF文件。我正在处理1500个点的气候日常观测数据,每个点的观测次数约为18250次。
问题是NetCDF文件的结构(create.ncdf)占用了4Gb,而每个点都会使文件大小增加超过3 Gb(put.var.ncdf)。
这是我正在使用的代码:
这是我正在使用的代码:
# Make a few dimensions we can use
dimX <- dim.def.ncdf( "Long", "degrees", Longvector )
dimY <- dim.def.ncdf( "LAT", "degrees", Latvector )
dimT <- dim.def.ncdf( "Time", "days", 1:18250, unlim=FALSE )
# Make varables of various dimensionality, for illustration purposes
mv <- -9999 # missing value to use
var1d <- var.def.ncdf( "var1d", "units", dimX, mv,prec="double" )
var2d <- var.def.ncdf( "var2d", "units", list(dimX,dimY), mv,prec="double" )
var3d <- var.def.ncdf( "var3d", "units", list(dimX,dimY,dimT), mv,prec="double" )
# Create the test file
nc <- create.ncdf( "writevals.nc", list(var1d,var2d,var3d) )
# !!Creates a nc file with + 4 Gb
# Adding the complete time series for one point (the first point in the list of the dataset)
put.var.ncdf( nc, var3d,dataset[[1]], start=c(Longvector[1],Latvector[1],1), count=c(1,1,-1))
Longvector和Latvector是从矩阵中取出的向量,每个点的经度和纬度都有对应的值。数据集采用列表格式,每个点都有一组数值列表。
dataset[[1]]=c(0,0,0,9.7,0,7.5,3.6,2.9,0,0.5,....)
我有所遗漏吗?还是应该尝试其他软件包?