Unexpected failure in spectro completeness notebook

[weaverba137]

In onskydata/spectro_completeness.ipynb, the cell that begins

z = []
fba = []
exp_fba = []
target = []
zmtl = []

throws an exception when run on Perlmutter with kernel 22.2 or 23.1. The full output from the cell is:

failed for redrock file from petal 1, tileid 4117 and night 20221122
failed for redrock file from petal 5, tileid 4117 and night 20221122
failed for zmtl file from petal 1, tileid 4117 and night 20221122
failed for zmtl file from petal 5, tileid 4117 and night 20221122
failed for redrock file from petal 1, tileid 5648 and night 20220324
failed for redrock file from petal 7, tileid 8776 and night 20220104
failed for zmtl file from petal 7, tileid 8776 and night 20220104
failed for redrock file from petal 7, tileid 8777 and night 20220104
failed for zmtl file from petal 7, tileid 8777 and night 20220104
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
Cell In[6], line 45
     42             print("failed for zmtl file from petal {}, tileid {} and night {}".format(petal, tileid, lastnight))
     44 data_z = np.hstack(z)
---> 45 data_fba = np.hstack(fba)
     46 data_exp_fba = np.hstack(exp_fba)
     47 data_target = np.hstack(target)

File <__array_function__ internals>:180, in hstack(*args, **kwargs)

File /global/common/software/desi/perlmutter/desiconda/20230111-2.1.0/conda/lib/python3.10/site-packages/numpy/core/shape_base.py:343, in hstack(tup)
    341 # As a special case, dimension 0 of 1-dimensional arrays is "horizontal"
    342 if arrs and arrs[0].ndim == 1:
--> 343     return _nx.concatenate(arrs, 0)
    344 else:
    345     return _nx.concatenate(arrs, 1)

File <__array_function__ internals>:180, in concatenate(*args, **kwargs)

TypeError: invalid type promotion with structured datatype(s).

[sbailey]

For DR1 I'm moving this ticket to "low priority" since it isn't in the core set of 01_getting_started or 02_digging_deeper tutorials, and the tutorials documentation specifically says that tutorials in other directories aren't actively maintained and may not longer work. i.e. we could still fix this at some point, but it is lower priority than the ones we must do for DR1.