Solved by vmirly1 in post #2 
              
              
                You should use torch.matmul instead of *, otherwise, it will do elementwise-product. I have a working example for a symmetric matrix: 
>>> A = [[4.4103, 0.2161, 0.5112],
         [0.2161, 3.8596, 0.7494],
         [0.5112, 0.7494, 3.7300]]
>>> A = torch.tensor(A)
# Display A:
>>> A
tensor([[4.4103,…