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Re: Question about Java NetCDF API usage

At 02:21 AM 5/28/2004, Ed Yu wrote:

I need to create a pretty large netcdf file (a combined
topology/bathymetry map). The x, y dimensions is around 7000 x 9000 (it
might even grow bigger in the future). I wanted to know if there is a
way to incrementally write the dimensions and the data out without
storing everything in an array before writing the data out. In addition,
I need to flush the data out in chunks to prevent running out of memory
(for the x, y dimensions and data).

Can this be done with the Java interface? If not, what interface
supports this kind of activity (perl/fortran/C)? Or can it even be done
at all?
I do not know what a topology/bathymetry map is, but I can offer a solution that we use for large data sets. What we have are multiple instances of a 2D data block, so the third dimension is variable. Essentially what we are doing is writing a "page" of 2D data for each calculation step. If you write the 2D block in one call, and retrieve it the same way, the execution time is very good. If you write the 2D array element by element, and retrieve it that way, the execution time is glacial.
If you want more specific information about what we're doing, I can post our source or e-mail it to you. 

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Lyn Greenhill, P.E.
DynaTech Engineering, Inc.