Debugging Numpy VisibleDeprecationWarning (ndarray from ragged nested sequences)

With a function that creates a ragged array:

In [60]: def foo():     ...:     print('one')     ...:     x = np.array([[1],[1,2]])     ...:     return x     ...:                                                                                             In [61]: foo()                                                                                       one/usr/local/bin/ipython3:3: VisibleDeprecationWarning: Creating an ndarray from ragged nested sequences (which is a list-or-tuple of lists-or-tuples-or ndarrays with different lengths or shapes) is deprecated. If you meant to do this, you must specify 'dtype=object' when creating the ndarray  # -*- coding: utf-8 -*-Out[61]: array([list([1]), list([1, 2])], dtype=object)

I get the warning, but also the expected result.

I can control the warnings.

For example to turn if off:

In [68]: np.warnings.filterwarnings('ignore', category=np.VisibleDeprecationWarning)                 In [69]: foo()                                                                                       oneOut[69]: array([list([1]), list([1, 2])], dtype=object)

Or to raise an error:

In [70]: np.warnings.filterwarnings('error', category=np.VisibleDeprecationWarning)                  In [71]: foo()                                                                                       one---------------------------------------------------------------------------VisibleDeprecationWarning                 Traceback (most recent call last)<ipython-input-71-c19b6d9633cf> in <module>----> 1 foo()<ipython-input-60-6ad21d9e07b4> in foo()      1 def foo():      2     print('one')----> 3     x = np.array([[1],[1,2]])      4     return x      5 VisibleDeprecationWarning: Creating an ndarray from ragged nested sequences (which is a list-or-tuple of lists-or-tuples-or ndarrays with different lengths or shapes) is deprecated. If you meant to do this, you must specify 'dtype=object' when creating the ndarray

The error gives a traceback telling me where the warning was raised.

There may be ways of refining the warning filter to catch just this one, and not others of the same category. I haven't used this mechanism much.

Read np.warnings.filterwarnings docs for more details.

b2 = np.array(    [[1, 2, 3, 4, 5, 6, 7, 8, 9, 10], [11, 12, 13, 14, 15, 16, 17, 18]],    dtype=object,)

Reference to the above example will clear the warning. You must specify dtype=object.

This warning is caused by deprecated API of NumPy version 1.19 or higher, you may continue using it and just suppress the warning:

import warningswarnings.filterwarnings("ignore", category=np.VisibleDeprecationWarning)