hi keith: Unidata Support wrote:
------- Forwarded MessageFrom: Keith Davidson <address@hidden> Subject: netcdf java setGlobalAttribute Organization: WNI Keywords: 200107110538.f6B5ce105368 netCDF javaDear Sir/Madam,Is there any reason why the NetCDF Java API does not include methods to modify global attributes?I find this very strange (apart from the fact that this can already be done in C, Fortran...), since NetCDF is a self describing format, and since it is possible to modify the data in the file, then surely the ability to modify the description of that data is essential.
An early design decision was to make Attributes immutable. The underlying problem is that arbitrary changes to attributes can in some cases force an entire rewrite of the file. So currently attributes can only be added at file creation time.
I personally agree with your sentiments, and we are looking for ways to allow attribute modification and additions. It will require some major refactoring; possibly it cant happen until we transition to a new netcdf file format (most likely hdf). So for now we are stuck with it.
One possible workaround for now is to explicitly rewrite the file, after specifying any attribute changes and addition. We could add some extra methods to make this convenient to the user. If this would be useful to you, please let us know, and we will add it to our "to do" list. ANy details of how you would use it would be helpful.