add support for qft algorithm

torchquantum/algorithm/__init__.py

@@ -23,4 +23,5 @@
 """
 
 from .vqe import *
-from .hamiltonian import *
+from .hamiltonian import *
+from .qft import *

torchquantum/algorithm/qft.py

@@ -0,0 +1,32 @@
+import torchquantum as tq
+from typing import Iterable
+
+__all__ = ["QFT"]
+
+class QFT(object):
+    def __init__(
+        self, n_wires: int = None, wires: Iterable = None, do_swaps=True
+    ) -> None:
+        """Init function for QFT class
+
+        Args:
+            n_wires (int): Number of wires for the QFT as an integer
+            wires (Iterable): Wires to perform the QFT as an Iterable
+            add_swaps (bool): Whether or not to add the final swaps in a boolean format
+            inverse (bool): Whether to create an inverse QFT layer in a boolean format
+        """
+        super().__init__()
+
+        self.n_wires = n_wires
+        self.wires = wires
+        self.do_swaps = do_swaps
+
+    def construct_qft_circuit(self) -> tq.QuantumModule:
+        """Construct the QFT circuit."""
+        return tq.layer.QFTLayer(n_wires=self.n_wires, wires=self.wires, do_swaps=self.do_swaps)
+
+    def construct_inverse_qft_circuit(self) -> tq.QuantumModule:
+        """Construct the inverse of a QFT circuit."""
+        return tq.layer.QFTLayer(
+            n_wires=self.n_wires, wires=self.wires, do_swaps=self.do_swaps, inverse=True
+        )