[File] Add a density-measurements.py file.

Author: Zhuoyang Ye

torchquantum/measurement/density_measurements.py

@@ -0,0 +1,69 @@
+import random
+
+import torch
+import torchquantum as tq
+import torchquantum.functional as tqf
+import numpy as np
+from torchquantum.macro import F_DTYPE
+
+from typing import Union, List
+from collections import Counter, OrderedDict
+
+from torchquantum.functional import mat_dict
+# from .operator import op_name_dict, Observable
+import torchquantum.operator as op
+from copy import deepcopy
+import matplotlib.pyplot as plt
+
+__all__ = [
+    "expval_joint_sampling_grouping",
+    "expval_joint_analytical",
+    "expval_joint_sampling",
+    "expval",
+    "measure",
+]
+
+
+def measure(noisedev: tq.NoiseDevice, n_shots=1024, draw_id=None):
+    return
+
+
+
+def expval_joint_sampling_grouping(
+        qdev: tq.NoiseDevice,
+        observables: List[str],
+        n_shots_per_group=1024,
+):
+    return
+
+
+def expval_joint_sampling(
+        qdev: tq.NoiseDevice,
+        observable: str,
+        n_shots=1024,
+):
+    return
+
+
+def expval_joint_analytical(
+        qdev: tq.NoiseDevice,
+        observable: str,
+):
+    return
+
+
+def expval(
+        qdev: tq.NoiseDevice,
+        wires: Union[int, List[int]],
+        observables: Union[op.Observable, List[op.Observable]],
+):
+    return
+
+
+
+
+
+
+
+if __name__ == '__main__':
+    print("")

torchquantum/measurement/measurements.py

@@ -43,13 +43,7 @@ def measure(qdev, n_shots=1024, draw_id=None):
         distribution of bitstrings
     """
     bitstring_candidates = gen_bitstrings(qdev.n_wires)
-    if isinstance(qdev, tq.QuantumDevice):
-        state_mag = qdev.get_states_1d().abs().detach().cpu().numpy()
-    elif isinstance(qdev, tq.NoiseDevice):
-        '''
-        Measure the density matrix in the computational basis
-        '''
-        state_mag = qdev.get_probs_1d().abs().detach().cpu().numpy()
+    state_mag = qdev.get_states_1d().abs().detach().cpu().numpy()
     distri_all = []
 
     for state_mag_one in state_mag: