title: writing netcdf parallel files from only certain processors
body: <p>I've come across a specific task to create a netcdf file which stores data only from certain processors. The matter is the following-I have 3d field, divided into (nx) x (ny) x (nz) domains. Each domain has a processor assigned to it. I would like to save data only from domains in certain position in x direction. This means that the data would come only from ny x nz processors. I've been trying to find examples on how to write such data, but unsucessfully. Does anyone know if this is doable and also-are there specific commands I should use. </p>
  
  <p>For example, I tried to invoke writing data with using if conditions where I used if(mpid%rank==0) then... together with nf90_var_par_access(ncid, varid, nf90_independent) call, but without success, the procedure seems to get stuck. </p>
  
  <p>thank you in advance!</p>