uczenie_maszynowe_zadania/cw_1/Untitled.ipynb

import numpy as np

arr = np.arange(float(1),float(17)).reshape(4,4)
mat = np.matrix(arr)

Macierze

print(arr)
print(mat)

[[ 1.  2.  3.  4.]
 [ 5.  6.  7.  8.]
 [ 9. 10. 11. 12.]
 [13. 14. 15. 16.]]
[[ 1.  2.  3.  4.]
 [ 5.  6.  7.  8.]
 [ 9. 10. 11. 12.]
 [13. 14. 15. 16.]]

print(arr**-1)
print(mat**-1)

[[1.         0.5        0.33333333 0.25      ]
 [0.2        0.16666667 0.14285714 0.125     ]
 [0.11111111 0.1        0.09090909 0.08333333]
 [0.07692308 0.07142857 0.06666667 0.0625    ]]

---------------------------------------------------------------------------
LinAlgError                               Traceback (most recent call last)
Cell In [22], line 2
      1 print(arr**-1)
----> 2 print(mat**-1)

File ~/.local/lib/python3.8/site-packages/numpy/matrixlib/defmatrix.py:231, in matrix.__pow__(self, other)
    230 def __pow__(self, other):
--> 231     return matrix_power(self, other)

File <__array_function__ internals>:180, in matrix_power(*args, **kwargs)

File ~/.local/lib/python3.8/site-packages/numpy/linalg/linalg.py:643, in matrix_power(a, n)
    640     return a
    642 elif n < 0:
--> 643     a = inv(a)
    644     n = abs(n)
    646 # short-cuts.

File <__array_function__ internals>:180, in inv(*args, **kwargs)

File ~/.local/lib/python3.8/site-packages/numpy/linalg/linalg.py:545, in inv(a)
    543 signature = 'D->D' if isComplexType(t) else 'd->d'
    544 extobj = get_linalg_error_extobj(_raise_linalgerror_singular)
--> 545 ainv = _umath_linalg.inv(a, signature=signature, extobj=extobj)
    546 return wrap(ainv.astype(result_t, copy=False))

File ~/.local/lib/python3.8/site-packages/numpy/linalg/linalg.py:88, in _raise_linalgerror_singular(err, flag)
     87 def _raise_linalgerror_singular(err, flag):
---> 88     raise LinAlgError("Singular matrix")

LinAlgError: Singular matrix