[Bug]: Heat operators eq, ne should allow non-array operands

[ClaudiaComito]

What happened?

Relational operators in Heat are treated as binary (element-wise) operations just like arithmetic operations. It follows that, currently, only array-like operands are supported.

This is overly restrictive, we want to be able to run comparisons similar to those shown below without raising an exception:

import heat as ht

>>> a = ht.arange(10)
>>> a == slice(None)
False
>>> a == ...
False
>>> a != slice(None)
True
>>> a != ...
True

Code snippet triggering the error

import heat as ht

a = ht.arange(10)
a == slice(None)

Error message or erroneous outcome

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/c.comito/devel/local/heat/heat/core/relational.py", line 76, in <lambda>
    DNDarray.__eq__ = lambda self, other: eq(self, other)
  File "/Users/c.comito/devel/local/heat/heat/core/relational.py", line 60, in eq
    res = _operations.__binary_op(torch.eq, x, y)
  File "/Users/c.comito/devel/local/heat/heat/core/_operations.py", line 82, in __binary_op
    raise TypeError(
TypeError: Only DNDarrays and numeric scalars are supported, but input was <class 'slice'>

Version

1.3.x

Python version

3.10

PyTorch version

2.0

MPI version

doesn't matter

[github-actions]

This issue is stale because it has been open for 60 days with no activity.