keeping multiple flags in netCDF CF conventions file

[petejan]

CNDC_quality_control_io:  The name of QC variable 'CNDC_quality_control_io' should end in '_quality_control'.
PSAL_quality_control_gr:  The name of QC variable 'PSAL_quality_control_gr' should end in '_quality_control'.
PSAL_quality_control_io:  The name of QC variable 'PSAL_quality_control_io' should end in '_quality_control'.
TEMP_quality_control_gr:  The name of QC variable 'TEMP_quality_control_gr' should end in '_quality_control'.
TEMP_quality_control_io:  The name of QC variable 'TEMP_quality_control_io' should end in '_quality_control'.

alternative

<VAR>_gr_quality_control
<VAR>_io_quality_control
<VAR>_quality_control

Naming of quality_control variables

check_quality_control_variable_standard_name

Quality control variables are identified by

check_quality_control_conventions_for_quality_control_variable

identifies quality control variables by the 'quality_control_conventions' attribute

Working example from PAR file

 float PAR(TIME) ;
 		PAR:_FillValue = NaNf ;
 		PAR:sensor_SeaVoX_L22_code = "SDN:L22::TOOL0193" ;
 		PAR:comment_sensor_type = "cosine sensor" ;
 		PAR:units = "umol/m^2/s" ;
 		PAR:calibration_date = "May 21, 2009" ;
 		PAR:calibration_units = "umol s-1 m-2 per uamp" ;
 		PAR:calibration_constant = "6.26" ;
 		PAR:calibration_multiplier = "-159.74" ;
 		PAR:calibration_resistor = "604" ;
 		PAR:comment_scaling_issue = "unknown scaling, due to missing resistor on data logging to convert current to voltage" ;
 		PAR:coordinates = "TIME LATITUDE LONGITUDE NOMINAL_DEPTH" ;
 		PAR:valid_max = 10000.f ;
 		PAR:valid_min = -2.f ;
 		PAR:comment_scale_offset_applied = "scale = 0.26447 offset = 0.0" ;
 		PAR:standard_name = "surface_downwelling_photosynthetic_photon_flux_in_air" ;
 		PAR:long_name = "surface_downwelling_photosynthetic_photon_flux_in_air" ;
 		PAR:ancillary_variables = "PAR_quality_control PAR_quality_control_io PAR_quality_control_gr PAR_quality_control_cl PAR_quality_control_man" ;
 	byte PAR_quality_control(TIME) ;
 		PAR_quality_control:_FillValue = 99b ;
 		PAR_quality_control:long_name = "quality flag for surface_downwelling_photosynthetic_photon_flux_in_air" ;
 		PAR_quality_control:standard_name = "surface_downwelling_photosynthetic_photon_flux_in_air status_flag" ;
 		PAR_quality_control:quality_control_conventions = "IMOS standard flags" ;
 		PAR_quality_control:flag_values = 0b, 1b, 2b, 3b, 4b, 6b, 7b, 9b ;
 		PAR_quality_control:flag_meanings = "unknown good_data probably_good_data probably_bad_data bad_data not_deployed interpolated missing_value" ;
 		PAR_quality_control:comment = "maximum of all flags" ;
 	byte PAR_quality_control_io(TIME) ;
 		PAR_quality_control_io:_FillValue = 99b ;
 		PAR_quality_control_io:long_name = "in/out of water flag for surface_downwelling_photosynthetic_photon_flux_in_air" ;
 		PAR_quality_control_io:units = "1" ;
 		PAR_quality_control_io:comment = "data flagged not deployed (6) when out of water" ;
 	byte PAR_quality_control_gr(TIME) ;
 		PAR_quality_control_gr:_FillValue = 99b ;
 		PAR_quality_control_gr:long_name = "global_range flag for surface_downwelling_photosynthetic_photon_flux_in_air" ;
 		PAR_quality_control_gr:units = "1" ;
 		PAR_quality_control_gr:comment = "Test 4. gross range test" ;
 	byte PAR_quality_control_cl(TIME) ;
 		PAR_quality_control_cl:_FillValue = 99b ;
 		PAR_quality_control_cl:long_name = "climate flag for surface_downwelling_photosynthetic_photon_flux_in_air" ;
 		PAR_quality_control_cl:units = "1" ;
 		PAR_quality_control_cl:comment = "Test 7. climatology test" ;
 		PAR_quality_control_cl:comment_note = "cosine sensor, par < (2 * SOLAR) + 15" ;
 	byte PAR_quality_control_man(TIME) ;
 		PAR_quality_control_man:_FillValue = 99b ;
 		PAR_quality_control_man:long_name = "manual flag for surface_downwelling_photosynthetic_photon_flux_in_air" ;
 		PAR_quality_control_man:units = "1" ;
 		PAR_quality_control_man:comment = "manual by date, after 2010-03-05" ;