In [1]: import numpy as np

In [2]: x = np.zeros((0, 50))

In [3]: np.nanargmin(x)
---------------------------------------------------------------------------
ValueError                                Traceback (most recent call last)
Cell In[3], line 1
----> 1 np.nanargmin(x)

File ~/.anaconda/envs/numpydev/lib/python3.10/site-packages/numpy/lib/nanfunctions.py:552, in nanargmin(a, axis, out, keepdims)
    550     mask = np.all(mask, axis=axis)
    551     if np.any(mask):
--> 552         raise ValueError("All-NaN slice encountered")
    553 res = np.argmin(a, axis=axis, out=out, keepdims=keepdims)
    554 return res

ValueError: All-NaN slice encountered

In [1]: import numpy as np

In [2]: x = np.zeros((0, 50))

In [3]: np.nanargmin(x)
---------------------------------------------------------------------------
ValueError                                Traceback (most recent call last)
Cell In[3], line 1
----> 1 np.nanargmin(x)

File ~/.anaconda/envs/numpydev/lib/python3.10/site-packages/numpy/lib/nanfunctions.py:553, in nanargmin(a, axis, out, keepdims)
    551     if np.any(mask):
    552         raise ValueError("All-NaN slice encountered")
--> 553 res = np.argmin(a, axis=axis, out=out, keepdims=keepdims)
    554 return res

File ~/.anaconda/envs/numpydev/lib/python3.10/site-packages/numpy/core/fromnumeric.py:1325, in argmin(a, axis, out, keepdims)
   1238 """
   1239 Returns the indices of the minimum values along an axis.
   1240 
   (...)
   1322 (2, 1, 4)
   1323 """
   1324 kwds = {'keepdims': keepdims} if keepdims is not np._NoValue else {}
-> 1325 return _wrapfunc(a, 'argmin', axis=axis, out=out, **kwds)

File ~/.anaconda/envs/numpydev/lib/python3.10/site-packages/numpy/core/fromnumeric.py:59, in _wrapfunc(obj, method, *args, **kwds)
     56     return _wrapit(obj, method, *args, **kwds)
     58 try:
---> 59     return bound(*args, **kwds)
     60 except TypeError:
     61     # A TypeError occurs if the object does have such a method in its
     62     # class, but its signature is not identical to that of NumPy's. This
   (...)
     66     # Call _wrapit from within the except clause to ensure a potential
     67     # exception has a traceback chain.
     68     return _wrapit(obj, method, *args, **kwds)

ValueError: attempt to get argmin of an empty sequence