There seems to be continued problems with the application of rewrite rules, though it is less clear exactly what rules are causing problems as I can't replicate the issue in the editor - they emerge from hsimplify. Specifically I find if I apply zx.hsimplify.hpivot_simp(circle, quiet=True) to the graph derived from the json below I arrive at a very different matrix, which shouldn't be possible. I am also of the opinion that something is off with the scalars but I can't quite tell if this is related to the errors in the transformations.
circle_json = '{"wire_vertices": {"b0": {"annotation": {"boundary": true, "coord": [10.37171875, -1.8646875], "input": false, "output": true}}, "b1": {"annotation": {"boundary": true, "coord": [11.04171875, -4.8796875], "input": false, "output": true}}, "b2": {"annotation": {"boundary": true, "coord": [-0.23828125, -1.2296874999999998], "input": true, "output": false}}, "b3": {"annotation": {"boundary": true, "coord": [-0.23828125, -4.7796875], "input": true, "output": false}}}, "node_vertices": {"v0": {"annotation": {"coord": [1.45171875, -0.12468749999999984]}, "data": {"type": "X"}}, "v1": {"annotation": {"coord": [1.51171875, -1.7046875]}, "data": {"type": "Z"}}, "v2": {"annotation": {"coord": [1.53671875, -4.6546875]}, "data": {"type": "Z"}}, "v3": {"annotation": {"coord": [1.6867187499999998, -3.0046875]}, "data": {"type": "hadamard", "is_edge": "false", "value": "\\pi"}}, "v4": {"annotation": {"coord": [3.0267187499999997, -0.024687500000000195]}, "data": {"type": "X"}}, "v5": {"annotation": {"coord": [2.50171875, -0.7246874999999999]}, "data": {"type": "hadamard", "is_edge": "false", "value": "\\pi"}}, "v6": {"annotation": {"coord": [2.42671875, -4.8496875]}, "data": {"type": "Z"}}, "v7": {"annotation": {"coord": [3.80171875, -4.7496875]}, "data": {"type": "Z"}}, "v8": {"annotation": {"coord": [2.17671875, -1.9996874999999998]}, "data": {"type": "Z"}}, "v9": {"annotation": {"coord": [3.22671875, -2.0246874999999998]}, "data": {"type": "Z"}}, "v10": {"annotation": {"coord": [2.7017187500000004, -2.049687499999999]}, "data": {"type": "X"}}, "v11": {"annotation": {"coord": [3.00171875, -4.8246875]}, "data": {"type": "X"}}, "v12": {"annotation": {"coord": [3.85171875, -0.09968749999999993]}, "data": {"type": "Z"}}, "v13": {"annotation": {"coord": [5.50171875, -0.024687500000000195]}, "data": {"type": "Z"}}, "v14": {"annotation": {"coord": [5.461718750000001, -1.9496875]}, "data": {"type": "Z"}}, "v15": {"annotation": {"coord": [4.83671875, -4.8746875]}, "data": {"type": "Z"}}, "v16": {"annotation": {"coord": [6.421718749999999, -1.9346875]}, "data": {"type": "Z"}}, "v17": {"annotation": {"coord": [6.356718749999999, -5.0996875]}, "data": {"type": "Z"}}, "v18": {"annotation": {"coord": [4.51171875, -2.049687499999999]}, "data": {"type": "X", "value": "\\pi"}}, "v19": {"annotation": {"coord": [5.956718750000001, -2.0096875]}, "data": {"type": "X", "value": "\\pi"}}, "v20": {"annotation": {"coord": [4.34671875, -5.0046875]}, "data": {"type": "X", "value": "\\pi"}}, "v21": {"annotation": {"coord": [5.611718749999999, -4.9496875]}, "data": {"type": "X", "value": "\\pi"}}, "v22": {"annotation": {"coord": [5.73171875, -3.6996874999999996]}, "data": {"type": "Z"}}, "v23": {"annotation": {"coord": [6.956718750000001, -3.4346875]}, "data": {"type": "Z"}}, "v24": {"annotation": {"coord": [5.26171875, -3.2996875]}, "data": {"type": "hadamard", "is_edge": "false", "value": "\\pi"}}, "v25": {"annotation": {"coord": [6.28171875, -3.3346875000000002]}, "data": {"type": "hadamard", "is_edge": "false", "value": "\\pi"}}, "v26": {"annotation": {"coord": [0.88671875, -1.3546874999999998]}, "data": {"type": "X", "value": "\\pi"}}, "v27": {"annotation": {"coord": [0.81171875, -4.7546875]}, "data": {"type": "X", "value": "\\pi"}}, "v28": {"annotation": {"coord": [2.87671875, -1.0496875]}, "data": {"type": "hadamard", "is_edge": "false", "value": "3\\pi/2"}}, "v29": {"annotation": {"coord": [3.4017187499999997, -0.9646875000000001]}, "data": {"type": "hadamard", "is_edge": "false", "value": "3\\pi/2"}}, "v30": {"annotation": {"coord": [3.87671875, -0.9996874999999998]}, "data": {"type": "hadamard", "is_edge": "false", "value": "3\\pi/2"}}, "v31": {"annotation": {"coord": [2.5767187500000004, -3.9496874999999996]}, "data": {"type": "hadamard", "is_edge": "false", "value": "\\pi/2"}}, "v32": {"annotation": {"coord": [3.1517187499999997, -3.6746875]}, "data": {"type": "hadamard", "is_edge": "false", "value": "\\pi/2"}}, "v33": {"annotation": 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