cdutil.averager should print an error message when called with 'irregular' data

[chaosphere2112]

cdutil.averager should print an explicit error message when the data is on a grid it can't handle

Ideally, of course, cdutil.averager should be able to handle data on non-rectilinear grids!

One of our post-docs got the following when trying to get a global average of a CMIP5 file on the ORCA ocean grid. The sample data file (and other files with non rectilinear grids) can be downloaded from: https://files.lsce.ipsl.fr/public.php?service=files&t=ca134197a67c3cd311df6ede04747f6f

>>> import cdms2, cdutil

>>> f = cdms2.open('ORCA_grid_sample.nc')
Warning: bounds variable not found in ORCA_grid_sample.nc: time_centered_bounds
Warning: bounds variable not found in ORCA_grid_sample.nc: time_centered_bounds

>>> v = f('sosstsst', squeeze=1)

>>> v.shape
(149, 182)

>>> v.info()
*** Description of Slab sosstsst ***
id: sosstsst
shape: (149, 182)
filename: 
missing_value: 1e+20
comments: 
grid_name: grid_2
grid_type: CurvilinearGrid
time_statistic: 
long_name: sea surface temperature
units: degC
_FillValue: [  1.00000002e+20]
autoApiInfo: <AutoAPI.AutoAPI.Info instance at 0x7fa4dd4a8e60>
interval_write: 1mo
tileIndex: None
coordinates: time_centered nav_lon nav_lat
online_operation: average
cell_methods: time_counter: mean
interval_operation: 3600s
Grid has Python id 0x7fa4dd930850.
** Dimension 1 **
   id: y
   units:  
   Length: 149
   First:  0.0
   Last:   148.0
   Python id:  0x7fa4dd930890
** Dimension 2 **
   id: x
   units:  
   Length: 182
   First:  0.0
   Last:   181.0
   Python id:  0x7fa4dd930910
*** End of description for sosstsst ***

>>> global_average = cdutil.averager(v, axis='yx')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/install/cdat/versions/cdat_install_uv-2.1.0_x86_64_gcc4_VB_13/lib/python2.7/site-packages/genutil/averager.py", line 1042, in averager
    axis_order = _check_axisoptions(V, axis)
  File "/usr/local/install/cdat/versions/cdat_install_uv-2.1.0_x86_64_gcc4_VB_13/lib/python2.7/site-packages/genutil/averager.py", line 25, in _check_axisoptions
    raise AveragerError, 'Error: You have specified an invalid axis= option.'
genutil.averager.AveragerError: ('E', 'r', 'r', 'o', 'r', ':', ' ', 'Y', 'o', 'u', ' ', 'h', 'a', 'v', 'e', ' ', 's', 'p', 'e', 'c', 'i', 'f', 'i', 'e', 'd', ' ', 'a', 'n', ' ', 'i', 'n', 'v', 'a', 'l', 'i', 'd', ' ', 'a', 'x', 'i', 's', '=', ' ', 'o', 'p', 't', 'i', 'o', 'n', '.')

>>> global_average = cdutil.averager(v, axis='12')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/install/cdat/versions/cdat_install_uv-2.1.0_x86_64_gcc4_VB_13/lib/python2.7/site-packages/genutil/averager.py", line 1042, in averager
    axis_order = _check_axisoptions(V, axis)
  File "/usr/local/install/cdat/versions/cdat_install_uv-2.1.0_x86_64_gcc4_VB_13/lib/python2.7/site-packages/genutil/averager.py", line 25, in _check_axisoptions
    raise AveragerError, 'Error: You have specified an invalid axis= option.'
genutil.averager.AveragerError: ('E', 'r', 'r', 'o', 'r', ':', ' ', 'Y', 'o', 'u', ' ', 'h', 'a', 'v', 'e', ' ', 's', 'p', 'e', 'c', 'i', 'f', 'i', 'e', 'd', ' ', 'a', 'n', ' ', 'i', 'n', 'v', 'a', 'l', 'i', 'd', ' ', 'a', 'x', 'i', 's', '=', ' ', 'o', 'p', 't', 'i', 'o', 'n', '.')

Migrated from: CDAT/cdat#1464

[github-actions]

Marking issue as stale, since there has been no activity in 30 days.

Unless the issue is updated or the 'stale' tag is removed, this issue will be closed in 7 days.

[durack1]

@jasonb5 this is another issue which will require the same tweaks as CDAT/genutil#6

[github-actions]

Marking issue as stale, since there has been no activity in 30 days.

Unless the issue is updated or the 'stale' tag is removed, this issue will be closed in 7 days.