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[netCDF #UUT-620101]: ARM float format

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  • Subject: [netCDF #UUT-620101]: ARM float format
  • Date: Mon, 11 Feb 2008 14:25:19 -0700
Hi Warren,

> 1) Are there no tests in nctest that try to read back the value from
> the file to make sure it is what was written there? (The unit tests
> don't seem to fail.)

The nc_test program writes thousands of values to the file and reads
them back to make sure they are the same values that were written.
For example, the function test_nc_get_var_float in nc_test/test_get.c
(generated from the macro preprocessor source in test_get.m4) opens a
netCDF file written by the function test_nc_put_var_float in
nc_test/test_put.c, generated from test_put.m4.  When you run the
nc_test/nc_test program, it logs all these tests:

  ...
 *** Testing nc_get_var_float ...  1216 good comparisons. ok
 *** Testing nc_get_var_double ...  1216 good comparisons. ok
 *** Testing nc_get_var1_text ...  179 good comparisons. ok
 *** Testing nc_get_var1_uchar ...  264 good comparisons. ok
 *** Testing nc_get_var1_schar ...  269 good comparisons. ok
 *** Testing nc_get_var1_short ...  718 good comparisons. ok
 *** Testing nc_get_var1_int ...  1216 good comparisons. ok
 *** Testing nc_get_var1_long ...  1216 good comparisons. ok
 *** Testing nc_get_var1_float ...  1216 good comparisons. ok
 *** Testing nc_get_var1_double ...  1216 good comparisons. ok
 *** Testing nc_get_var1 ...  1395 good comparisons. ok
 *** Testing nc_get_vara_text ...  179 good comparisons. ok
 *** Testing nc_get_vara_uchar ...  264 good comparisons. ok
 *** Testing nc_get_vara_schar ...  269 good comparisons. ok
 *** Testing nc_get_vara_short ...  718 good comparisons. ok
 *** Testing nc_get_vara_int ...  1216 good comparisons. ok
 *** Testing nc_get_vara_long ...  1216 good comparisons. ok
  ...

Are these the tests in which you are seeing the failures with ARM?

There are also lots of similar tests in nctest, for example see the
functions test_varputget1 in nctest/vartests.c and the test_varputget
function in nctest/vputget.c.  Do these tests succeed when you run
the nctest program from that directory?

> 2) Could proper support be added for the ARM platform?

Yes, but we would need a testing platform to see what's wrong and
fix it.

> BTW, I built an ARM qemu virtual machine to figure some of this stuff
> how. If you want the qemu files to run it yourself, let me know.

If that would be a good testing platform, we'd like to get it.  Are there
Fortran and C++ compilers available for that virtual machine also?

I've just been adding correct handling of IEEE NaNs and Infinity values to
ncdump, so I may need to do something special for the ARM platfomr in that
case. also.

Thanks for reporting the problem.

--Russ



Russ Rew                                         UCAR Unidata Program
address@hidden                     http://www.unidata.ucar.edu



Ticket Details
===================
Ticket ID: UUT-620101
Department: Support netCDF
Priority: Normal
Status: Closed