updating docs, and cleaning up imports

docs/deutsch_jozsa.rst

@@ -11,7 +11,7 @@ either 1 or 0, and a balanced function maps to 1 for half of the inputs and maps
 half. Unlike any deterministic classical algorithm, the Deutsch-Jozsa Algorithm can solve this
 problem with a single iteration, regardless of the input size. It was one of the first known quantum
 algorithms that showed an exponential speedup, albeit against a deterministic (non-probabilistic)
-classical computer, and with access to a blackbox function that can evaluate inputs to the chosen
+classical compuetwr, and with access to a blackbox function that can evaluate inputs to the chosen
 function.
 
 Algorithm and Details
@@ -48,6 +48,16 @@ Algorithm:
   #. Measure :math:`\ket{x}`. If the result is all zeroes, then the function is constant. Otherwise, it
      is balanced.
 
+Implementation Notes
+--------------------
+
+The oracle in the :term:`Deutsch-Jozsa` module is not implemented in such a way that calling
+`Deutsch_Jozsa.is_constant()` will yield an exponential speedup over classical implementations.  To
+construct the quantum algorithm that is executing on the QPU we use a Quil `defgate`, which
+specifies the circuit :math:`U_w` as its action on the data qubits :math:`\ket{x}`. This matrix is
+exponentially large, and thus even generating the program will take exponential time.
+
+
 Source Code Docs
 ----------------
 

grove/deutsch_jozsa/deutsch_jozsa.py

@@ -18,14 +18,15 @@
 """
 import numpy as np
 import pyquil.quil as pq
-from pyquil.gates import *
+from pyquil.gates import X, H, CNOT
 
 
 SWAP_MATRIX = np.array([[1, 0, 0, 0],
                         [0, 0, 1, 0],
                         [0, 1, 0, 0],
                         [0, 0, 0, 1]])
 r"""The matrix that performs \alpha\ket{ij}\to\alpha\ket{ji}"""
+
 ORACLE_GATE_NAME = "DEUTSCH_JOZSA_ORACLE"
 
 
@@ -92,7 +93,6 @@ def _construct_deutsch_jozsa_circuit(self):
         dj_prog.inst(X(self.ancillas[0]), H(self.ancillas[0]))
 
         # Apply Hadamard, Oracle, and Hadamard again
-
         dj_prog.inst([H(qubit) for qubit in self.computational_qubits])
 
         # Build the oracle