NetCDF 到栅格砖 "Unable to find inherited method for function 'brick' for 'ncdf4'"

Question

栅格包的真正简单问题，也使用 ncdf4 加载 ECMWF Era-Interim Netcdf 文件。

只需这样做：

a <- nc_open("SSTs.nc")
B <- brick(a, varname="sst")

Returns这个：

    Error in (function (classes, fdef, mtable)  : 
  unable to find an inherited method for function ‘brick’ for signature ‘"ncdf4"’

该文件是全球1个月（2016年1月）的SST数据。当我将它转换成一个数组时（即提取 dimensions/variable，并将时间转换为 UTC，将它推入一个数组）我没有得到同样的错误，但是光栅包说它直接支持 .nc 文件（只要它们与 cf-1 兼容，Era-Interim .nc 就是）

非常感谢任何帮助，已尝试使用许多 Netcdf 文件（非 Era Interim）。

Answer 1

感谢Renaud Lancelot，谁给的清楚源码。我修改了他的代码以适应您的数据

 # load package
 library(sp)
 library(raster)
 library(ncdf4)

 # read ncdf file
 nc<-nc_open('D:/SSTs.nc')

 # extract variable name, size and dimension
 v <- nc$var[[1]]
 size <- v$varsize
 dims <- v$ndims
 nt <- size[dims]              # length of time dimension
 lat <- nc$dim$latitude$vals   # latitude position
 lon <- nc$dim$longitude$vals  # longitude position

 # read sst variable
 r<-list()
 for (i in 1:nt) {
   start <- rep(1,dims)     # begin with start=(1,1,...,1)
   start[dims] <- i             # change to start=(1,1,...,i) to read    timestep i
   count <- size                # begin with count=(nx,ny,...,nt), reads entire var
   count[dims] <- 1             # change to count=(nx,ny,...,1) to read 1 tstep

   dt<-ncvar_get(nc, varid = 'sst', start = start, count = count)

   # convert to raster
   r[i]<-raster(dt)
 }

 # create layer stack with time dimension
 r<-stack(r)

 # transpose the raster to have correct orientation
 rt<-t(r)
 extent(rt)<-extent(c(range(lon), range(lat)))

 # plot the result
 spplot(rt)

NetCDF 到栅格砖 "Unable to find inherited method for function 'brick' for 'ncdf4'"

NetCDF to Raster Brick "Unable to find inherited method for function 'brick' for 'ncdf4'"

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raster

netcdf