Merge 9daf3e4 into 23f79eb

doc/source/_apidoc/qutip_qip.decompose.rst

@@ -0,0 +1,21 @@
+qutip\_qip.decompose package
+============================
+
+Submodules
+----------
+
+qutip\_qip.decompose.single\_qubit\_gate module
+-----------------------------------------------
+
+.. automodule:: qutip_qip.decompose.single_qubit_gate
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+Module contents
+---------------
+
+.. automodule:: qutip_qip.decompose
+   :members:
+   :undoc-members:
+   :show-inheritance:

doc/source/_apidoc/qutip_qip.rst

@@ -9,6 +9,7 @@ Subpackages
 
    qutip_qip.algorithms
    qutip_qip.compiler
+   qutip_qip.decompose
    qutip_qip.device
    qutip_qip.operations
    qutip_qip.transpiler
@@ -72,6 +73,14 @@ qutip\_qip.qubits module
    :undoc-members:
    :show-inheritance:
 
+qutip\_qip.version module
+-------------------------
+
+.. automodule:: qutip_qip.version
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
 Module contents
 ---------------
 

src/qutip_qip/circuit.py

@@ -49,7 +49,7 @@
 )
 from .operations.gates import _gate_label
 from qutip import basis, ket2dm, qeye
-from qutip.qobj import Qobj
+from qutip import Qobj
 from qutip.measurement import measurement_statistics
 
 
@@ -2130,3 +2130,30 @@ def _apply_measurement(self, operation):
         else:
             raise NotImplementedError(
                 "mode {} is not available.".format(self.mode))
+
+# For Decomposition functions
+def decomposed_gates_to_circuit(decomposed_gate,num_qubits):
+    """This function takes the input from a decomposition function and returns
+    a quantum circuit.
+    """
+    # as decomposed_gate contains information about targets/control, there's no
+    # additional input of target here.
+    # In addition, there's no check if the gates are valid for number of qubits
+    # because this is done in a decomposition function before output.
+    if isinstance(decomposed_gate,tuple) == True:
+        q_circuit = QubitCircuit(num_qubits, reverse_states=False)
+        for i in decomposed_gate:
+            q_circuit.add_gate(i)
+        return(q_circuit)
+    else:
+        raise TypeError("Input is not a tuple of gates.")
+
+def compute_unitary(quantum_circuit):
+    """Evaluates all the gates in the quantum circuit.
+    """
+    if isinstance(quantum_circuit, QubitCircuit) == True:
+        gate_list = quantum_circuit.propagators()
+        matrix_of_all_gates = gate_sequence_product(gate_list)
+        return(matrix_of_all_gates)
+    else:
+        raise TypeError("Input is not of type QubitCircuit.")

src/qutip_qip/decompose/__init__.py

@@ -0,0 +1 @@
+from .single_qubit_gate import *

src/qutip_qip/decompose/_utility.py

@@ -0,0 +1,39 @@
+import numpy as np
+import cmath
+
+from qutip import Qobj
+
+class MethodError(Exception):
+    """When invalid method is chosen, this error is raised.
+    """
+    pass
+
+class GateError(Exception):
+    """When chosen method cannot be applied to the input gate, this error
+    is raised.
+    """
+    pass
+
+
+def check_gate(gate, num_qubits):
+    """Verifies input is a valid quantum gate.
+
+    Parameters
+    ----------
+    gate : :class:`qutip.Qobj`
+        The matrix that's supposed to be decomposed should be a Qobj.
+    num_qubits:
+        Number of qubits in the circuit.
+    Raises
+    ------
+    TypeError
+        If the gate is not a Qobj.
+    ValueError
+        If the gate is not a unitary operator on qubits.
+    """
+    if not isinstance(gate, Qobj):
+        raise TypeError("The input matrix is not a Qobj.")
+    if not gate.check_isunitary():
+        raise ValueError("Input is not unitary.")
+    if gate.dims != [[2] * num_qubits] * 2:
+        raise ValueError(f"Input is not a unitary on {num_qubits} qubits.")