From b4872397e9ce2abc912fc55d27f45909ace4b742 Mon Sep 17 00:00:00 2001
From: Pete Shadbolt <pete.shadbolt@gmail.com>
Date: Mon, 4 Jul 2016 21:48:14 +0100
Subject: [PATCH] Progress towards working measurement

---
 .gitignore                |  1 +
 abp/clifford.py           |  2 +-
 abp/graphstate.py         | 24 ++++++++++++++++++++++--
 abp/util.py               |  4 ++++
 tests/test_measurement.py | 15 +++++----------
 5 files changed, 33 insertions(+), 13 deletions(-)

diff --git a/.gitignore b/.gitignore
index 0ec9d42..144aa78 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,4 @@
+.noseids
 debug_anders.txt
 *.o
 *.chp
diff --git a/abp/clifford.py b/abp/clifford.py
index 28fe836..af5885a 100644
--- a/abp/clifford.py
+++ b/abp/clifford.py
@@ -6,7 +6,7 @@ It provides tables for Clifford group multiplication and conjugation,
 as well as CZ and decompositions of the 2x2 Cliffords.
 """
 
-import os, json, tempfile, os, sys, json, string
+import os, json, tempfile, json
 from functools import reduce
 import itertools as it
 import numpy as np
diff --git a/abp/graphstate.py b/abp/graphstate.py
index 66bcdcf..4573fb1 100644
--- a/abp/graphstate.py
+++ b/abp/graphstate.py
@@ -117,6 +117,26 @@ class GraphState(object):
         if new_edge != edge:
             self.toggle_edge(a, b)
 
+    def measure(self, node, basis, force=None):
+        """ Measure in an arbitrary basis """
+        basis = clifford.by_name[basis]
+        old_basis = basis
+        ha = clifford.conjugation_table[self.node[node]["vop"]]
+        basis, phase = clifford.conjugate(basis, ha)
+        print basis, phase
+        assert phase in (-1, 1) # TODO: remove
+
+        # TODO: wtf
+        force = force ^ 0x01 if force != -1 and phase == 0 else force
+
+        which = {1: self.measure_x, 2: self.measure_y, 3: self.measure_z}[basis]
+        res = which(node, force)
+        res = res if phase == 1 else not res
+
+        # TODO: put the asserts from graphsim.cpp into tests
+        return res
+
+
     def measure_z(self, node, force=None):
         """ Measure the graph in the Z-basis """
         res = force if force != None else random.choice([0, 1])
@@ -136,12 +156,12 @@ class GraphState(object):
 
         return res
 
-    def measure_x(self, i):
+    def measure_x(self, node, force=None):
         """ Measure the graph in the X-basis """
         # TODO
         pass
 
-    def measure_y(self, i):
+    def measure_y(self, node, force=None):
         """ Measure the graph in the Y-basis """
         # TODO
         pass
diff --git a/abp/util.py b/abp/util.py
index b4e15f6..a468b14 100644
--- a/abp/util.py
+++ b/abp/util.py
@@ -1,2 +1,6 @@
+""" 
+Utility functions for ABP
+"""
+
 def xyz(x, y, z=0):
     return {"x": x, "y": y, "z": z}
diff --git a/tests/test_measurement.py b/tests/test_measurement.py
index 01eb0f0..d164c1f 100644
--- a/tests/test_measurement.py
+++ b/tests/test_measurement.py
@@ -8,13 +8,8 @@ def test_z_measurement():
 
 
 def test_z_measurement_against_ab():
-    a = graphsim.GraphRegister(1)
-    b = GraphState()
-    b.add_node(0)
-
-    print a.measure(0, graphsim.lco_Z)
-    print b.measure_z(0)
-
-
-
-
+    for i in range(100):
+        a = graphsim.GraphRegister(1)
+        b = GraphState()
+        b.add_node(0)
+        assert a.measure(0, graphsim.lco_Z) == b.measure(0, "pz")