netCDF4 file not readable by cdms2

[durack1]

The (1.7Gb) file at crunch:~duro/tmp/vmro3_input4MIPs_ozone_DAMIP_CCMI-hist-stratO3-1-0_gr_185001-189912.nc is not readable by cdms2 - the following error occurs upon attempting to open the file:

(uvcdat2100nox) duro@ocean:[DavidPlummer_Ozone]:[4695]> ipython                                                                 
Python 2.7.13 | packaged by conda-forge | (default, May  2 2017, 12:48:11)                                                             

In [1]: import cdms2 as cdm
In [2]: f = '170728/vmro3_input4MIPs_ozone_DAMIP_CCMI-hist-stratO3-1-0_gr_185001-189912.nc'
In [3]: fH = cdm.open(f)
---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
<ipython-input-3-4b0a2899c811> in <module>()                               
----> 1 fH = cdm.open(f)                                                   

/export/duro/anaconda2/envs/uvcdat2100nox/lib/python2.7/site-packages/cdms2/dataset.pyc in openDataset(uri, mode, template, dods, dpath, hostObj)                                                                                                                          
    364                                                                                                                                
    365             # The file exists                                                                                                  
--> 366             file1 = CdmsFile(path, "r")                                                                                        
    367             if libcf is not None:                                                                                              
    368                 if hasattr(file1, libcf.CF_FILETYPE):                                                                          

/export/duro/anaconda2/envs/uvcdat2100nox/lib/python2.7/site-packages/cdms2/dataset.pyc in __init__(self, path, mode, hostObj, mpiBarrier)                                                                                                                                 
   1177                 # (latname,lonname,order,maskname, abstract_class).                                                            
   1178                 gridkey, lat, lon = var.generateGridkey(                                                                       
-> 1179                     self._convention_, self.variables)                                                                         
   1180                                                                                                                                
   1181                 # If the variable is gridded, lookup the grid. If no such grid exists,                                         

/export/duro/anaconda2/envs/uvcdat2100nox/lib/python2.7/site-packages/cdms2/avariable.pyc in generateGridkey(self, convention, vardict)                                                                                                                                    
    241             or (None, None, None) if not gridded. vardict is the variable dictionary of the parent"""                          
    242                                                                                                                                
--> 243         lat, nlat = convention.getVarLatId(self, vardict)                                                                      
    244         lon, nlon = convention.getVarLonId(self, vardict)                                                                      
    245         if (lat is not None) and (lat is lon):                                                                                 

/export/duro/anaconda2/envs/uvcdat2100nox/lib/python2.7/site-packages/cdms2/convention.pyc in getVarLatId(self, var, vardict)
    172                     nlat += 1                                                                                           
    173         if lat is None:                                                                                                 
--> 174             lat, nlat = AbstractConvention.getVarLatId(self, var, vardict)                                              
    175                                                                                                                         
    176         return (lat, nlat)                                                                                              

/export/duro/anaconda2/envs/uvcdat2100nox/lib/python2.7/site-packages/cdms2/convention.pyc in getVarLatId(self, var, vardict)
     56                                                                                                                         
     57         for obj in [d[0] for d in var.getDomain()]:                                                                     
---> 58             if self.axisIsLatitude(obj):                                                                                
     59                 if nlat == 0:                                                                                           
     60                     lat = obj                                                                                           

/export/duro/anaconda2/envs/uvcdat2100nox/lib/python2.7/site-packages/cdms2/convention.pyc in axisIsLatitude(self, axis)
    204         if (hasattr(axis, 'axis') and axis.axis == 'Y'):                                                           
    205             return True                                                                                            
--> 206         elif (hasattr(axis, 'units') and string.lower(axis.units) in ['degrees_north',                             
    207                                                                       'degree_north',                                          
    208                                                                       'degree_n',                                              

/export/duro/anaconda2/envs/uvcdat2100nox/lib/python2.7/string.pyc in lower(s)
    226                                                                          
    227     """                                                                  
--> 228     return s.lower()                                                     
    229                                                                          
    230 # Convert lower case letters to UPPER CASE                               

AttributeError: 'list' object has no attribute 'lower'

File ncdump:
vmro3_input4MIPs_ozone_DAMIP_CCMI-hist-stratO3-1-0_gr_185001-189912.txt

[durack1]

I have attempted to extract a single timestep using CDO and this works, and attempting to read the file using netcdf4-python also works fine

[durack1]

It also seems that NCO 4.6.7 also doesn't quite like this format - but does provide an output:

(uvcdat2100nox) duro@ocean:[DavidPlummer_Ozone]:[4581]> ncks -O -d time,1
170728/vmro3_input4MIPs_ozone_DAMIP_CCMI-hist-stratO3-1-0_gr_185001-189912.nc
vmro3_input4MIPs_ozone_DAMIP_CCMI-hist-stratO3-1-0_gr_185001_nco.nc
ncks: WARNING the "bounds" attribute for variable lon is type NC_STRING, not NC_CHAR.
This violates the CF convention for specifying additional attributes.
Therefore nco_is_spc_in_cf_att() will skip this attribute. NB: To avoid excessive noise,
NCO prints this WARNING at most once per dataset.

[dnadeau4]

Can you send the ncdump?

[dnadeau4]

It seems from the error message that your axis.units is a list and not a string. Can send ncdump -h of the latitude axis today ? (I don't have my laptop)

[durack1]

@dnadeau4, the ncdump is an attachment above (top comment)

[dnadeau4]

#150