Add state initialization implementation in initilization.py

python-impl/initilization/initilization.py

@@ -0,0 +1,54 @@
+import math
+from qiskit import QuantumCircuit, transpile
+from qiskit.providers.basic_provider import BasicSimulator
+
+
+###############################################################
+# Make a quantum circuit for state initialization.
+###############################################################
+circuit = QuantumCircuit(4, 4, name="initializer_circ")
+
+desired_vector = [
+    1 / math.sqrt(4) * complex(0, 1),
+    1 / math.sqrt(8) * complex(1, 0),
+    0,
+    0,
+    0,
+    0,
+    0,
+    0,
+    1 / math.sqrt(8) * complex(1, 0),
+    1 / math.sqrt(8) * complex(0, 1),
+    0,
+    0,
+    0,
+    0,
+    1 / math.sqrt(4) * complex(1, 0),
+    1 / math.sqrt(8) * complex(1, 0),
+]
+
+circuit.initialize(desired_vector, [0, 1, 2, 3])
+
+circuit.measure([0, 1, 2, 3], [0, 1, 2, 3])
+
+print(circuit)
+
+###############################################################
+# Execute on a simulator backend.
+###############################################################
+shots = 10000
+
+# Desired vector
+print("Desired probabilities: ")
+print([format(abs(x * x), ".3f") for x in desired_vector])
+
+# Initialize on local simulator
+sim_backend = BasicSimulator()
+job = sim_backend.run(transpile(circuit, sim_backend), shots=shots)
+result = job.result()
+
+counts = result.get_counts(circuit)
+
+qubit_strings = [format(i, "04b") for i in range(2**4)]
+print("Probabilities from simulator: ")
+print([format(counts.get(s, 0) / shots, ".3f") for s in qubit_strings])