Standardize the output format of qml.specs

doc/releases/changelog-dev.md

@@ -207,6 +207,10 @@
 
 <h3>Breaking changes 💔</h3>
 
+* The output format of `qml.specs` has been restructured into a dataclass to streamline the outputs.
+  Some legacy information has been removed from the new output format.
+  [(#8713)](https://github.com/PennyLaneAI/pennylane/pull/8713)
+
 * The unified compiler, implemented in the `qml.compiler.python_compiler` submodule, has been removed from PennyLane.
   It has been migrated to Catalyst, available as `catalyst.python_interface`.
   [(#8662)](https://github.com/PennyLaneAI/pennylane/pull/8662)

pennylane/devices/_qubit_device.py

@@ -44,15 +44,13 @@
     SampleMeasurement,
     SampleMP,
     ShadowExpvalMP,
-    Shots,
     StateMeasurement,
     StateMP,
     VarianceMP,
     VnEntropyMP,
 )
 from pennylane.operation import Operation, Operator, operation_derivative
 from pennylane.ops import MeasurementValue, MidMeasure, Rot, X, Y, Z, adjoint
-from pennylane.resource import Resources
 from pennylane.tape import QuantumScript
 from pennylane.wires import Wires
 
@@ -314,19 +312,11 @@ def execute(self, circuit, **kwargs):
         self._num_executions += 1
 
         if self.tracker.active:
-            shots_from_dev = self._shots if not self.shot_vector else self._raw_shot_sequence
-            tape_resources = circuit.specs["resources"]
-
-            resources = Resources(  # temporary until shots get updated on tape !
-                tape_resources.num_wires,
-                tape_resources.num_gates,
-                tape_resources.gate_types,
-                tape_resources.gate_sizes,
-                tape_resources.depth,
-                Shots(shots_from_dev),
-            )
             self.tracker.update(
-                executions=1, shots=self._shots, results=results, resources=resources
+                executions=1,
+                shots=self._shots,
+                results=results,
+                resources=circuit.specs["resources"],
             )
             self.tracker.record()
 

pennylane/resource/__init__.py

@@ -1,4 +1,4 @@
-# Copyright 2018-2022 Xanadu Quantum Technologies Inc.
+# Copyright 2018-2025 Xanadu Quantum Technologies Inc.
 
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -18,14 +18,8 @@
 .. seealso::
     The :mod:`~.estimator` module for higher level resource estimation of quantum programs.
 
-.. warning::
-    The functions ``estimate_error``, ``estimate_shots`` and the classes ``DoubleFactorization``,
-    ``FirstQuantization`` have been moved to the :mod:`pennylane.estimator` module.
-    Accessing them from the :mod:`pennylane.resource` module is deprecated and will be removed
-    in v0.45.
-
-Circuit specifications
-----------------------
+Circuit Specifications (specs)
+------------------------------
 
 .. currentmodule:: pennylane
 
@@ -34,6 +28,18 @@
 
     ~specs
 
+Circuit Specification Classes and Utilities
+-------------------------------------------
+
+.. currentmodule:: pennylane.resource
+
+.. autosummary::
+    :toctree: api
+
+    ~CircuitSpecs
+    ~SpecsResources
+
+    ~resources_from_tape
 
 Error Tracking
 --------------
@@ -47,6 +53,12 @@
     ~SpectralNormError
     ~ErrorOperation
 
+.. warning::
+    The functions ``estimate_error``, ``estimate_shots`` and the classes ``DoubleFactorization``,
+    ``FirstQuantization`` have been moved to the :mod:`pennylane.estimator` module.
+    Accessing them from the :mod:`pennylane.resource` module is deprecated and will be removed
+    in v0.45.
+
 Resource Classes
 ----------------
 
@@ -75,8 +87,8 @@
 Tracking Resources for Custom Operations
 ----------------------------------------
 
-We can use the :code:`null.qubit` device with the :class:`pennylane.Tracker` to track the resources
-used in a quantum circuit with custom operations without execution.
+We can use the :mod:`null.qubit <pennylane.devices.null_qubit>` device with the :class:`pennylane.Tracker`
+to track the resources used in a quantum circuit with custom operations without execution.
 
 .. code-block:: python
 
@@ -112,25 +124,32 @@ def circuit(theta):
 
 We can examine the resources by accessing the :code:`resources` key:
 
->>> resources_lst = tracker.history['resources']
->>> print(resources_lst[0])
-num_wires: 3
-num_gates: 7
-depth: 5
-shots: Shots(total=100)
-gate_types:
-{'RZ': 1, 'CNOT': 2, 'Hadamard': 2, 'PauliZ': 2}
-gate_sizes:
-{1: 5, 2: 2}
+    >>> resources_lst = tracker.history['resources']
+    >>> print(resources_lst[0])
+    Total qubit allocations: 3
+    Total gates: 7
+    Circuit depth: 5
+    <BLANKLINE>
+    Gate types:
+      RZ: 1
+      CNOT: 2
+      Hadamard: 2
+      PauliZ: 2
+    <BLANKLINE>
+    Measurements:
+      expval(PauliZ): 1
 """
 from .error import AlgorithmicError, ErrorOperation, SpectralNormError
 from .resource import (
     Resources,
     ResourcesOperation,
+    SpecsResources,
+    CircuitSpecs,
     add_in_series,
     add_in_parallel,
     mul_in_series,
     mul_in_parallel,
+    resources_from_tape,
     substitute,
 )
 from .specs import specs