重命名 netcdf 文件中的维度

renaming dimension in netcdf file

我是 nco 的初学者,如果能给我一些关于我的工作流程的建议以及一些帮助解决我正在努力解决的问题,我将不胜感激。

我有 these data,其中包含两个不同时间步长的 3D 盐度值:

dimensions:
    t = 780 ;
    z = 54 ;
    y = 450 ;
    x = 3600 ;
variables:
    double time(t) ;
        time:units = "days since 1-1-1 00:00:0.0" ;
    float level(z) ;
        level:units = "[m]" ;
    float lat(y) ;
    float lon(x) ;
    float salt(x, y, z) ;
        salt:units = "psu * 1000 + 35" ;
        salt:missingvalue = "-1.0E34" ;
        salt:longname = "salinity" ;

我想连接两个 netcdf 文件。

为此,我首先使用 ncecat *.nc -O merged.nc

dimensions:
    record = UNLIMITED ; // (2 currently)
    t = 780 ;
    z = 54 ;
    y = 450 ;
    x = 3600 ;
variables:
    double time(record, t) ;
        time:units = "days since 1-1-1 00:00:0.0" ;
    float level(record, z) ;
        level:units = "[m]" ;
    float lat(record, y) ;
    float lon(record, x) ;
    float salt(record, x, y, z) ;
        salt:units = "psu * 1000 + 35" ;
        salt:missingvalue = "-1.0E34" ;
        salt:longname = "salinity" ;

现在变量 time 和维度 t 是虚假的。所以,我用 ncks -O -x -v time merged.nc merged.nc:

删除它们
    record = UNLIMITED ; // (2 currently)
    y = 450 ;
    z = 54 ;
    x = 3600 ;
variables:
    float lat(record, y) ;
    float level(record, z) ;
        level:units = "[m]" ;
    float lon(record, x) ;
    float salt(record, x, y, z) ;
        salt:units = "psu * 1000 + 35" ;
        salt:missingvalue = "-1.0E34" ;
        salt:longname = "salinity" ;

现在,我想将维度 record 重命名为:ncrename -d record,time merged.nc。该命令运行时没有错误或警告。但是当我做 ncdump -h merged.nc 我得到这个 error:

ncdump: merged.nc: NetCDF: HDF error

这是什么意思?我哪里做错了?

编辑

按照 Charlie Zender

发布的答案
ncecat -O -u time *.nc merged.nc
ncks -O -x -v time merged.nc merged.nc

结果:

dimensions:
    time = UNLIMITED ; // (2 currently)
    y = 450 ;
    z = 54 ;
    x = 3600 ;
    t = 780 ;
variables:
    float lat(time, y) ;
    float level(time, z) ;
        level:units = "[m]" ;
    float lon(time, x) ;
    float salt(time, x, y, z) ;
        salt:units = "psu * 1000 + 35" ;
        salt:missingvalue = "-1.0E34" ;
        salt:longname = "salinity" ;
    double time(time, t) ;
        time:units = "days since 1-1-1 00:00:0.0" ;

// global attributes:
        :history = "Tue Jun  5 09:08:25 2018: ncks -O -x -v time merged.nc merged.nc\nTue Jun  5 09:08:19 2018: ncecat -O -u time OFES_salt_mmean_607.nc OFES_salt_mmean_608.nc merged.nc" ;
        :NCO = "netCDF Operators version 4.7.4 (http://nco.sf.net)" ;
        :nco_openmp_thread_number = 1 ;

首先我推荐的命令是

ncecat -O -u time *.nc merged.nc

这样就无需将 record 重命名为 time。那么

ncks -O -x -v time merged.nc merged.nc

这样行吗?

已编辑问题的答案:

关于 ncrename 收到的错误,您可能遇到了描述 here 的 netCDF4 库错误。推荐的解决方案是转换为 netCDF3,重命名,然后根据需要转换回 netCDF4:

ncks -3 in.nc out.nc
ncrename -d record,time out.nc
ncks -4 out.nc out.nc