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+--- Thread: The formula in the function is not giving the correct value (/thread-36779.html)
The formula in the function is not giving the correct value - quest - Mar-29-2022
Here is my function
def coefficients(_list,q_number):
paulis = list(product([i,x,y,z],repeat=q_number))
spaulis = list(product(['i','x','y','z'],repeat=q_number))
#print(spaulis)
result = []
for k_index,kraus in enumerate(_list,start=0):
print(kraus)
for index, pauli in enumerate(paulis, start=0):
a = 1/2*(np.trace(np.matmul(kraus,pauli)))
result.append((a,spaulis[index],k_index))
return resulti = np.array([[1, 0], [0, 1]]) x = np.array([[0, 1], [1, 0]]) y = np.array([[0,-1j],[1j,0]]) z = np.array([[1, 0], [0,-1]])Here is my example list:
krausf=np.array([[[-9.84447177e-01-7.67061139e-18j,
1.00575460e-03+1.82351449e-02j],
[-1.08968355e-03+6.25615662e-03j,
-9.78901978e-01-9.19498996e-03j]]]The formula is a = 1/2*(np.trace(np.matmul(kraus,pauli))), let'stake pauli=iI should find these result for i:
(-0.9816745775-0.004597494980000004j)
However, I am finding:
[-0.49222359-3.83530569e-18j, 0.00050288+9.11757245e-03j] from function. I can't see the point that I missed
What is happening?
RE: The formula in the function is not giving the correct value - quest - Mar-30-2022
This line a = 1/2*(np.trace(np.matmul(kraus,pauli))) should be a = 1/2*(np.trace(np.matmul(kraus,pauli[0])))