Split .nc file into multiple .nc files

Hallo everybody.

I'm looking for some help regarding: How to split a .nc-file into multiple .nc-files.

I downloaded satellite (different variables) data from ERA-Interim for a specific area (lat x lon: 16 x 34) for nearly 20 years (1992-2009). But I only received one single file. With ncdisp I can look at it, e.g. for the variable total rainfall:

    tp       
           Size:       16x34x6575
           Dimensions: longitude,latitude,time
           Datatype:   int16
           Attributes:
                       scale_factor  = 3.1821e-06
                       add_offset    = 0.10426
                       _FillValue    = -32767
                       missing_value = -32767
                       units         = 'm'
                       long_name     = 'Total precipitation'

The size of this 3D array is now 16x34x6575. The last number is a time vector equal to the days -> 6575 days. My question now: how can I 'split' this file into 6575 new files?

So at the moment I have this file: data.nc, but I want for every day a new file: data_19920101.nc to data_20091231.nc in my folder. One file should look like this:

tp       
           Size:       16x34x1
           Dimensions: longitude,latitude,time
           Datatype:   int16
           Attributes:
                       scale_factor  = 3.1821e-06
                       add_offset    = 0.10426
                       _FillValue    = -32767
                       missing_value = -32767
                       units         = 'm'
                       long_name     = 'Total precipitation'

I would be very thankful for any and all help.

Best

[anjula marasinghe]

did you find the answer. I have same question

Answer 1

[KSSV]

@anjula marasinghe, @Jake_K

There is no necessity to split the single ncfile into multiple ncfiles for each time step. It is waste of time, waste of task and not required. You can read the ncfile, at the required time step you want from the single file and use the data. You have two options, first read the file step by step in a loop. Second, load the entire data and pick what timestep you want.

Option 1

ncfile=myfile.nc ; 
lon = ncread(ncfile,'longitude') ; nx = length(lon) ; 
lat = ncread(ncfile,'latitude') ; ny = length(lat) ; 
time = ncread(ncfile,'time') ;
for i = 1:length(time)
    tp = ncread(ncfile,'tp',[1 1 i ],[nx ny 1]) ;
    pcolor(lon,lat,tp') ; 
    title(sprintf("Time step = %d",i)) ; 
    shading interp 
    drawnow
end

Option 2

ncfile=myfile.nc ; 
lon = ncread(ncfile,'longitude') ; nx = length(lon) ; 
lat = ncread(ncfile,'latitude') ; ny = length(lat) ; 
time = ncread(ncfile,'time') ;
tp = ncread(ncfile.'tp') ; 
for i = 1:length(time)
    R = tp(:,:,i) ;
    pcolor(lon,lat,R')
    shading interp 
    drawnow
end