fixed a bug for empty files

[givelberg]

Added testing for empty files and logging the number of obs.
The code exits if the filtering results in no data, so no output file is created.

[AndrewEichmann-NOAA]

Looks ok to me.

[emcbot]

Automated GW GDASApp Testing Results:
Machine: hera

Start: Fri Nov  1 16:27:54 UTC 2024 on hfe11
---------------------------------------------------
Build:                                 *SUCCESS*
Build: Completed at Fri Nov  1 17:17:22 UTC 2024
---------------------------------------------------
Tests:                                  *Failed*
Tests: Failed at Fri Nov  1 20:22:53 UTC 2024
Tests: 58% tests passed, 23 tests failed out of 55
	1955 - test_gdasapp_WCDA-3DVAR-C48mx500_gdas_marinebmat_202103241800 (Failed)
	1956 - test_gdasapp_WCDA-3DVAR-C48mx500_gdas_marineanlinit_202103241800 (Failed)
	1957 - test_gdasapp_WCDA-3DVAR-C48mx500_gdas_marineanlvar_202103241800 (Failed)
	1958 - test_gdasapp_WCDA-3DVAR-C48mx500_gdas_marineanlchkpt_202103241800 (Failed)
	1963 - test_gdasapp_atm_jjob_var_init (Failed)
	1964 - test_gdasapp_atm_jjob_var_run (Failed)
	1965 - test_gdasapp_atm_jjob_var_inc (Failed)
	1966 - test_gdasapp_atm_jjob_var_final (Failed)
	1971 - test_gdasapp_atm_jjob_ens_sol (Failed)
	1972 - test_gdasapp_atm_jjob_ens_inc (Failed)
	1973 - test_gdasapp_atm_jjob_ens_final (Failed)
	1975 - test_gdasapp_bufr2ioda_insitu_profile_argo (Failed)
	1976 - test_gdasapp_bufr2ioda_insitu_profile_bathy (Failed)
	1977 - test_gdasapp_bufr2ioda_insitu_profile_glider (Failed)
	1978 - test_gdasapp_bufr2ioda_insitu_profile_tesac (Failed)
	1979 - test_gdasapp_bufr2ioda_insitu_profile_tropical (Failed)
	1980 - test_gdasapp_bufr2ioda_insitu_profile_xbtctd (Failed)
	1981 - test_gdasapp_bufr2ioda_insitu_surface_drifter (Failed)
	1982 - test_gdasapp_bufr2ioda_insitu_surface_trkob (Failed)
Tests: see output at /scratch1/NCEPDEV/da/role.jedipara/CI/GDASApp/workflow/PR/1351/global-workflow/sorc/gdas.cd/build/log.ctest

[emcbot]

Automated GW GDASApp Testing Results:
Machine: hera

Start: Wed Nov  6 18:55:28 UTC 2024 on hfe02
---------------------------------------------------
Build:                                 *SUCCESS*
Build: Completed at Wed Nov  6 19:44:29 UTC 2024
---------------------------------------------------
Tests:                                  *Failed*
Tests: Failed at Wed Nov  6 20:21:07 UTC 2024
Tests: 78% tests passed, 12 tests failed out of 55
	1955 - test_gdasapp_WCDA-3DVAR-C48mx500_gdas_marinebmat_202103241800 (Failed)
	1956 - test_gdasapp_WCDA-3DVAR-C48mx500_gdas_marineanlinit_202103241800 (Failed)
	1957 - test_gdasapp_WCDA-3DVAR-C48mx500_gdas_marineanlvar_202103241800 (Failed)
	1958 - test_gdasapp_WCDA-3DVAR-C48mx500_gdas_marineanlchkpt_202103241800 (Failed)
	1959 - test_gdasapp_WCDA-3DVAR-C48mx500_gdas_marineanlfinal_202103241800 (Failed)
	1963 - test_gdasapp_atm_jjob_var_init (Failed)
	1964 - test_gdasapp_atm_jjob_var_run (Failed)
	1965 - test_gdasapp_atm_jjob_var_inc (Failed)
	1966 - test_gdasapp_atm_jjob_var_final (Failed)
	1971 - test_gdasapp_atm_jjob_ens_sol (Failed)
	1972 - test_gdasapp_atm_jjob_ens_inc (Failed)
	1973 - test_gdasapp_atm_jjob_ens_final (Failed)
Tests: see output at /scratch1/NCEPDEV/da/role.jedipara/CI/GDASApp/workflow/PR/1351/global-workflow/sorc/gdas.cd/build/log.ctest

[guillaumevernieres]

Thanks @givelberg . The ci failures are unrelated to your work.