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Wrap os.path functions in method calls Some functions from os.path are now references to C functions (e.g. isdir on Windows). This breaks the path module, because compiled functions do not get bound to an object instance. All os.path functions have been wrapped in method calls, out of general caution. Closes gh-737
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qerror.ipynb
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Quantum Error Correction

In [1]:
%load_ext sympyprinting
In [2]:
from sympy import sqrt, symbols, Rational
from sympy import expand, Eq, Symbol, simplify, exp, sin
from sympy.physics.quantum import *
from sympy.physics.quantum.qubit import *
from sympy.physics.quantum.gate import *
from sympy.physics.quantum.grover import *
from sympy.physics.quantum.qft import QFT, IQFT, Fourier
from sympy.physics.quantum.circuitplot import circuit_plot

5 qubit code

In [3]:
M0 = Z(1)*X(2)*X(3)*Z(4); M0
Out[3]:
$$Z_{1} X_{2} X_{3} Z_{4}$$
In [4]:
M1 = Z(2)*X(3)*X(4)*Z(0); M1
Out[4]:
$$Z_{2} X_{3} X_{4} Z_{0}$$
In [5]:
M2 = Z(3)*X(4)*X(0)*Z(1); M2
Out[5]:
$$Z_{3} X_{4} X_{0} Z_{1}$$
In [6]:
M3 = Z(4)*X(0)*X(1)*Z(2); M3
Out[6]:
$$Z_{4} X_{0} X_{1} Z_{2}$$

These operators should mutually commute.

In [7]:
gate_simp(Commutator(M0,M1).doit())
Out[7]:
$$0$$

And square to the identity.

In [8]:
for o in [M0,M1,M2,M3]:
    display(gate_simp(o*o))
$$1$$
$$1$$
$$1$$
$$1$$

Codewords

In [9]:
zero = Rational(1,4)*(1+M0)*(1+M1)*(1+M2)*(1+M3)*IntQubit(0, 5); zero
Out[9]:
$$\frac{1}{4} \left(1 + Z_{1} X_{2} X_{3} Z_{4}\right) \left(1 + Z_{2} X_{3} X_{4} Z_{0}\right) \left(1 + Z_{3} X_{4} X_{0} Z_{1}\right) \left(1 + Z_{4} X_{0} X_{1} Z_{2}\right) {\left|0\right\rangle }$$
In [10]:
qapply(4*zero)
Out[10]:
$${\left|0\right\rangle } + {\left|3\right\rangle } - {\left|5\right\rangle } + {\left|6\right\rangle } - {\left|9\right\rangle } - {\left|10\right\rangle } + {\left|12\right\rangle } - {\left|15\right\rangle } + {\left|17\right\rangle } - {\left|18\right\rangle } - {\left|20\right\rangle } - {\left|23\right\rangle } + {\left|24\right\rangle } - {\left|27\right\rangle } - {\left|29\right\rangle } - {\left|30\right\rangle }$$
In [11]:
one = Rational(1,4)*(1+M0)*(1+M1)*(1+M2)*(1+M3)*IntQubit(2**5-1, 5); one
Out[11]:
$$\frac{1}{4} \left(1 + Z_{1} X_{2} X_{3} Z_{4}\right) \left(1 + Z_{2} X_{3} X_{4} Z_{0}\right) \left(1 + Z_{3} X_{4} X_{0} Z_{1}\right) \left(1 + Z_{4} X_{0} X_{1} Z_{2}\right) {\left|31\right\rangle }$$
In [12]:
qapply(4*one)
Out[12]:
$$- {\left|1\right\rangle } - {\left|2\right\rangle } - {\left|4\right\rangle } + {\left|7\right\rangle } - {\left|8\right\rangle } - {\left|11\right\rangle } - {\left|13\right\rangle } + {\left|14\right\rangle } - {\left|16\right\rangle } + {\left|19\right\rangle } - {\left|21\right\rangle } - {\left|22\right\rangle } + {\left|25\right\rangle } - {\left|26\right\rangle } + {\left|28\right\rangle } + {\left|31\right\rangle }$$

The encoding circuit

In [13]:
encoding_circuit = H(3)*H(4)*CNOT(2,0)*CNOT(3,0)*CNOT(4,0)*H(1)*H(4)*\
                   CNOT(2,1)*CNOT(4,1)*H(2)*CNOT(3,2)*CNOT(4,2)*H(3)*\
                   H(4)*CNOT(4, 3)*Z(4)*H(4)*Z(4)
In [14]:
circuit_plot(encoding_circuit, nqubits=5, scale=0.5)
Out[14]:
<sympy.physics.quantum.circuitplot.CircuitPlot object at 0x38a6950>
No description has been provided for this image
In [15]:
represent(4*encoding_circuit, nqubits=5)
Out[15]:
$$\left(\begin{smallmatrix}1 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & 0 & -1 & 0 & -1 & 0 & -1 & 0 & -1 & 0 & -1 & 0 & -1 & 0 & -1 & 0 & -1 & -1 & 0 & -1 & 0 & -1 & 0 & -1 & 0\\0 & 1 & 0 & 1 & 0 & 1 & 0 & 1 & -1 & 0 & -1 & 0 & -1 & 0 & -1 & 0 & -1 & 0 & -1 & 0 & -1 & 0 & -1 & 0 & 0 & -1 & 0 & -1 & 0 & -1 & 0 & -1\\0 & 1 & 0 & -1 & 0 & 1 & 0 & -1 & -1 & 0 & 1 & 0 & -1 & 0 & 1 & 0 & -1 & 0 & 1 & 0 & -1 & 0 & 1 & 0 & 0 & -1 & 0 & 1 & 0 & -1 & 0 & 1\\1 & 0 & -1 & 0 & 1 & 0 & -1 & 0 & 0 & -1 & 0 & 1 & 0 & -1 & 0 & 1 & 0 & -1 & 0 & 1 & 0 & -1 & 0 & 1 & -1 & 0 & 1 & 0 & -1 & 0 & 1 & 0\\0 & -1 & 0 & -1 & 0 & 1 & 0 & 1 & 1 & 0 & 1 & 0 & -1 & 0 & -1 & 0 & -1 & 0 & -1 & 0 & 1 & 0 & 1 & 0 & 0 & -1 & 0 & -1 & 0 & 1 & 0 & 1\\-1 & 0 & -1 & 0 & 1 & 0 & 1 & 0 & 0 & 1 & 0 & 1 & 0 & -1 & 0 & -1 & 0 & -1 & 0 & -1 & 0 & 1 & 0 & 1 & -1 & 0 & -1 & 0 & 1 & 0 & 1 & 0\\1 & 0 & -1 & 0 & -1 & 0 & 1 & 0 & 0 & -1 & 0 & 1 & 0 & 1 & 0 & -1 & 0 & 1 & 0 & -1 & 0 & -1 & 0 & 1 & 1 & 0 & -1 & 0 & -1 & 0 & 1 & 0\\0 & 1 & 0 & -1 & 0 & -1 & 0 & 1 & -1 & 0 & 1 & 0 & 1 & 0 & -1 & 0 & 1 & 0 & -1 & 0 & -1 & 0 & 1 & 0 & 0 & 1 & 0 & -1 & 0 & -1 & 0 & 1\\0 & -1 & 0 & -1 & 0 & -1 & 0 & -1 & 1 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & -1 & 0 & -1 & 0 & -1 & 0 & -1 & 0 & 0 & -1 & 0 & -1 & 0 & -1 & 0 & -1\\-1 & 0 & -1 & 0 & -1 & 0 & -1 & 0 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & -1 & 0 & -1 & 0 & -1 & 0 & -1 & -1 & 0 & -1 & 0 & -1 & 0 & -1 & 0\\-1 & 0 & 1 & 0 & -1 & 0 & 1 & 0 & 0 & 1 & 0 & -1 & 0 & 1 & 0 & -1 & 0 & -1 & 0 & 1 & 0 & -1 & 0 & 1 & -1 & 0 & 1 & 0 & -1 & 0 & 1 & 0\\0 & -1 & 0 & 1 & 0 & -1 & 0 & 1 & 1 & 0 & -1 & 0 & 1 & 0 & -1 & 0 & -1 & 0 & 1 & 0 & -1 & 0 & 1 & 0 & 0 & -1 & 0 & 1 & 0 & -1 & 0 & 1\\1 & 0 & 1 & 0 & -1 & 0 & -1 & 0 & 0 & -1 & 0 & -1 & 0 & 1 & 0 & 1 & 0 & -1 & 0 & -1 & 0 & 1 & 0 & 1 & -1 & 0 & -1 & 0 & 1 & 0 & 1 & 0\\0 & 1 & 0 & 1 & 0 & -1 & 0 & -1 & -1 & 0 & -1 & 0 & 1 & 0 & 1 & 0 & -1 & 0 & -1 & 0 & 1 & 0 & 1 & 0 & 0 & -1 & 0 & -1 & 0 & 1 & 0 & 1\\0 & -1 & 0 & 1 & 0 & 1 & 0 & -1 & 1 & 0 & -1 & 0 & -1 & 0 & 1 & 0 & 1 & 0 & -1 & 0 & -1 & 0 & 1 & 0 & 0 & 1 & 0 & -1 & 0 & -1 & 0 & 1\\-1 & 0 & 1 & 0 & 1 & 0 & -1 & 0 & 0 & 1 & 0 & -1 & 0 & -1 & 0 & 1 & 0 & 1 & 0 & -1 & 0 & -1 & 0 & 1 & 1 & 0 & -1 & 0 & -1 & 0 & 1 & 0\\0 & 1 & 0 & 1 & 0 & 1 & 0 & 1 & 1 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & -1 & 0 & -1 & 0 & -1 & 0 & -1 & 0 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & 1\\1 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & -1 & 0 & -1 & 0 & -1 & 0 & -1 & 1 & 0 & 1 & 0 & 1 & 0 & 1 & 0\\-1 & 0 & 1 & 0 & -1 & 0 & 1 & 0 & 0 & -1 & 0 & 1 & 0 & -1 & 0 & 1 & 0 & 1 & 0 & -1 & 0 & 1 & 0 & -1 & -1 & 0 & 1 & 0 & -1 & 0 & 1 & 0\\0 & -1 & 0 & 1 & 0 & -1 & 0 & 1 & -1 & 0 & 1 & 0 & -1 & 0 & 1 & 0 & 1 & 0 & -1 & 0 & 1 & 0 & -1 & 0 & 0 & -1 & 0 & 1 & 0 & -1 & 0 & 1\\-1 & 0 & -1 & 0 & 1 & 0 & 1 & 0 & 0 & -1 & 0 & -1 & 0 & 1 & 0 & 1 & 0 & -1 & 0 & -1 & 0 & 1 & 0 & 1 & 1 & 0 & 1 & 0 & -1 & 0 & -1 & 0\\0 & -1 & 0 & -1 & 0 & 1 & 0 & 1 & -1 & 0 & -1 & 0 & 1 & 0 & 1 & 0 & -1 & 0 & -1 & 0 & 1 & 0 & 1 & 0 & 0 & 1 & 0 & 1 & 0 & -1 & 0 & -1\\0 & -1 & 0 & 1 & 0 & 1 & 0 & -1 & -1 & 0 & 1 & 0 & 1 & 0 & -1 & 0 & -1 & 0 & 1 & 0 & 1 & 0 & -1 & 0 & 0 & 1 & 0 & -1 & 0 & -1 & 0 & 1\\-1 & 0 & 1 & 0 & 1 & 0 & -1 & 0 & 0 & -1 & 0 & 1 & 0 & 1 & 0 & -1 & 0 & -1 & 0 & 1 & 0 & 1 & 0 & -1 & 1 & 0 & -1 & 0 & -1 & 0 & 1 & 0\\1 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & 1 & -1 & 0 & -1 & 0 & -1 & 0 & -1 & 0\\0 & 1 & 0 & 1 & 0 & 1 & 0 & 1 & 1 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & 0 & -1 & 0 & -1 & 0 & -1 & 0 & -1\\0 & -1 & 0 & 1 & 0 & -1 & 0 & 1 & -1 & 0 & 1 & 0 & -1 & 0 & 1 & 0 & -1 & 0 & 1 & 0 & -1 & 0 & 1 & 0 & 0 & 1 & 0 & -1 & 0 & 1 & 0 & -1\\-1 & 0 & 1 & 0 & -1 & 0 & 1 & 0 & 0 & -1 & 0 & 1 & 0 & -1 & 0 & 1 & 0 & -1 & 0 & 1 & 0 & -1 & 0 & 1 & 1 & 0 & -1 & 0 & 1 & 0 & -1 & 0\\0 & -1 & 0 & -1 & 0 & 1 & 0 & 1 & -1 & 0 & -1 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & -1 & 0 & -1 & 0 & 0 & -1 & 0 & -1 & 0 & 1 & 0 & 1\\-1 & 0 & -1 & 0 & 1 & 0 & 1 & 0 & 0 & -1 & 0 & -1 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & -1 & 0 & -1 & -1 & 0 & -1 & 0 & 1 & 0 & 1 & 0\\-1 & 0 & 1 & 0 & 1 & 0 & -1 & 0 & 0 & -1 & 0 & 1 & 0 & 1 & 0 & -1 & 0 & 1 & 0 & -1 & 0 & -1 & 0 & 1 & -1 & 0 & 1 & 0 & 1 & 0 & -1 & 0\\0 & -1 & 0 & 1 & 0 & 1 & 0 & -1 & -1 & 0 & 1 & 0 & 1 & 0 & -1 & 0 & 1 & 0 & -1 & 0 & -1 & 0 & 1 & 0 & 0 & -1 & 0 & 1 & 0 & 1 & 0 & -1\end{smallmatrix}\right)$$