Abdelpakey:

arr_numpy


This has to do with the rcond condition of the scipy null_space function. If you do not provide rcond it takes a weird default
if rcond is None:
        rcond = numpy.finfo(s.dtype).eps * max(M, N)

Here is a working code
import torch
from scipy.linalg import null_space
sw_bar_tensor=torch.FloatTensor(49, 49).to('cuda')
arr_numpy=sw_bar_tensor.detach().cpu().numpy()
null_space(arr_numpy,rcond=1.)

Result
array([[-1.74963553e-01,  0.00000000e+00],
       [ 4.51028104e-16, -9.12652367e-16],
       [ 2.33284737e-01,  1.45436634e-15],
       [ 1.38777878e-16, -1.54846174e-16],
       [ 1.16642369e-01,  9.48298648e-16],
       [ 5.55111512e-16, -1.01050836e-15],
       [ 7.07767178e-16,  4.64086501e-16],
       [ 2.26207941e-15, -3.16227766e-01],
       [ 1.74963553e-01,  7.21644966e-16],