refactored and optimized code (#9292)

* refactored and optimized code

* refactored code

* formatted the code

* undid changes
added comment explaining the deprecated logic

* reformatted using tox -e black

Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

examples/python/initialize.py

@@ -55,7 +55,7 @@
 
 # Desired vector
 print("Desired probabilities: ")
-print(str(list(map(lambda x: format(abs(x * x), ".3f"), desired_vector))))
+print(list(map(lambda x: format(abs(x * x), ".3f"), desired_vector)))
 
 # Initialize on local simulator
 sim_backend = BasicAer.get_backend("qasm_simulator")
@@ -64,6 +64,6 @@
 
 counts = result.get_counts(circuit)
 
-qubit_strings = [format(i, "0%sb" % 4) for i in range(2**4)]
+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])

qiskit/algorithms/amplitude_amplifiers/grover.py

@@ -308,7 +308,7 @@ def amplify(self, amplification_problem: AmplificationProblem) -> "GroverResult"
                 }
                 top_measurement, max_probability = max(circuit_results.items(), key=lambda x: x[1])
 
-            else:
+            else:  # use of else brach instead of elif as this seperates out the deprecated logic
                 if self._quantum_instance.is_statevector:
                     qc = self.construct_circuit(amplification_problem, power, measurement=False)
                     circuit_results = self._quantum_instance.execute(qc).get_statevector()