Added check for hybrid Control/Matrix Gate classes + test

Author: juanboschero

opensquirrel/squirrel_ir.py

@@ -7,10 +7,8 @@
 from typing import Callable, List, Optional, Tuple
 
 import numpy as np
-
 from opensquirrel.common import ATOL, X, Y, Z, normalize_angle, normalize_axis
 
-
 class SquirrelIRVisitor(ABC):
     def visit_comment(self, comment: "Comment"):
         pass
@@ -159,7 +157,6 @@ def is_identity(self) -> bool:
         # Angle and phase are already normalized.
         return abs(self.angle) < ATOL and abs(self.phase) < ATOL
 
-
 class MatrixGate(Gate):
     generator: Optional[Callable[..., "MatrixGate"]] = None
 
@@ -173,8 +170,10 @@ def __init__(self, matrix: np.ndarray, operands: List[Qubit], generator=None, ar
 
     def __eq__(self, other):
         # TODO: Determine whether we shall allow for a global phase difference here.
-        if not isinstance(other, MatrixGate):
+        if not isinstance(other, ControlledGate | MatrixGate):
             return False  # FIXME: a MatrixGate can hide a ControlledGate. https://github.com/QuTech-Delft/OpenSquirrel/issues/88
+        if isinstance(other,ControlledGate):
+            return _compare_gate_classes(self,other)
         return np.allclose(self.matrix, other.matrix)
 
     def __repr__(self):
@@ -200,8 +199,11 @@ def __init__(self, control_qubit: Qubit, target_gate: Gate, generator=None, argu
         self.target_gate = target_gate
 
     def __eq__(self, other):
-        if not isinstance(other, ControlledGate):
+       
+        if not isinstance(other, ControlledGate | MatrixGate):
             return False  # FIXME: a MatrixGate can hide a ControlledGate. https://github.com/QuTech-Delft/OpenSquirrel/issues/88
+        if isinstance(other, MatrixGate):
+            return _compare_gate_classes(self,other)
         if self.control_qubit != other.control_qubit:
             return False
 
@@ -220,7 +222,23 @@ def get_qubit_operands(self) -> List[Qubit]:
     def is_identity(self) -> bool:
         return self.target_gate.is_identity()
 
+def _get_qubit_num(gate: ControlledGate | MatrixGate) -> int:
+    operand = gate.get_qubit_operands()
+    return max(qubit.index for qubit in operand) + 1
+
+def _compare_gate_classes(g1: ControlledGate | MatrixGate, g2: ControlledGate | MatrixGate) -> bool:
+    
+    from opensquirrel.utils.matrix_expander import get_matrix
+    
+    matrix_g1 = get_matrix(g1, _get_qubit_num(g1))
+    matrix_g2 = get_matrix(g2, _get_qubit_num(g2))
+
+    if(matrix_g1.shape != matrix_g2.shape):
+        return False
+    
+    return np.allclose(matrix_g1, matrix_g2)
 
+    
 def named_gate(gate_generator: Callable[..., Gate]) -> Callable[..., Gate]:
     @wraps(gate_generator)
     def wrapper(*args, **kwargs):

opensquirrel/utils/__init__.py

@@ -0,0 +1,5 @@
+from opensquirrel.utils.matrix_expander import get_matrix
+
+__all__ = [
+    "get_matrix",
+]

test/utils/test_matrix_expander.py

@@ -75,3 +75,23 @@ def test_matrix_gate(self):
                 ),
             )
         )
+
+
+    def test_gate_equality(self):
+        cnot_matrix_gate = MatrixGate(
+            np.array(
+                [
+                    [1, 0, 0, 0],
+                    [0, 1, 0, 0],
+                    [0, 0, 0, 1],
+                    [0, 0, 1, 0],
+                ]
+            ),
+            operands=[Qubit(1), Qubit(2)]
+        )
+
+        cnot_controlled_gate = ControlledGate(
+            Qubit(1), BlochSphereRotation(qubit=Qubit(2), axis=(1, 0, 0), angle=math.pi, phase=math.pi / 2)
+        )
+
+        self.assertTrue(cnot_controlled_gate == cnot_matrix_gate)