sherman_morrison¶
Sherman–Morrison formula.
This modifies A_inv inplace.
Parameters¶
-
A_inv (dict)
-
u (dict)
-
v (dict)
Examples¶
>>> import pprint
>>> from river import utils
>>> A_inv = {
... (0, 0): 0.2,
... (1, 1): 1,
... (2, 2): 1
... }
>>> u = {0: 1, 1: 2, 2: 3}
>>> v = {0: 4}
>>> inv = sherman_morrison(A_inv, u, v)
>>> pprint.pprint(inv)
{(0, 0): 0.111111,
(1, 0): -0.888888,
(1, 1): 1,
(2, 0): -1.333333,
(2, 2): 1}