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Re: adding time-invariant variables to a netCDF file

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  • Subject: Re: adding time-invariant variables to a netCDF file
  • Date: Fri, 23 Apr 1999 17:36:30 -0600
Rick:

You should have recieved a patch to netcdf/libsrc/posixio.c
which appears to fix the problem you reported. Thank you
for providing a test case.

For your information, your program will run about twice as fast
if you add the flag NC_ALIGN_CHUNK to nc_open(). If you use this flag
on your initial nc_create, the redef may take almost no time.

Beyond NC_ALIGN_CHUNK, you can use nc__open() (two underbars) and fool
around with the 'chunksizehint' parameter and get at least another
factor of two out of it.

-glenn