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Description
I am using tfq.layers.PQC and tfq.layers.ControlledPQC extensively, but say I don't want to check the expectation value of the qubit state rather just want to check what's the output of the state (might be in tf.Tensor form). In tfq.layers.PQC (and tfq.layers.ControlledPQC) we have got an attribute by the name of operators which measures the expectation value of the qubit state in Z basis, if the operator is chosen to be cirq.Z(cirq.GridQubit))?
I tried using operators = [] but ended up having an error which is probably related to this operators attribute.
[/usr/local/lib/python3.8/dist-packages/tensorflow/python/autograph/impl/api.py](https://localhost:8080/#) in wrapper(*args, **kwargs)
697 except Exception as e: # pylint:disable=broad-except
698 if hasattr(e, 'ag_error_metadata'):
--> 699 raise e.ag_error_metadata.to_exception(e)
700 else:
701 raise
TypeError: Exception encountered when calling layer "discriminator_3" (type Discriminator).
in user code:
File "<ipython-input-46-be27fbd4a19d>", line 30, in call *
quantum_output = self.quantum_operation([tiled_circuits, quantum_inputs])
File "/usr/local/lib/python3.8/dist-packages/keras/utils/traceback_utils.py", line 67, in error_handler **
raise e.with_traceback(filtered_tb) from None
TypeError: Exception encountered when calling layer "controlled_pqc_5" (type ControlledPQC).
in user code:
File "/usr/local/lib/python3.8/dist-packages/tensorflow_quantum/python/layers/high_level/controlled_pqc.py", line 264, in call *
return self._layer(model_appended,
File "/usr/local/lib/python3.8/dist-packages/keras/utils/traceback_utils.py", line 67, in error_handler **
raise e.with_traceback(filtered_tb) from None
TypeError: Exception encountered when calling layer "expectation_5" (type Expectation).
in user code:
File "/usr/local/lib/python3.8/dist-packages/tensorflow_quantum/python/layers/circuit_executors/expectation.py", line 357, in call *
operators)
File "/usr/local/lib/python3.8/dist-packages/tensorflow_quantum/python/differentiators/differentiator.py", line 156, in op_wrapper_analytic
forward_pass_vals = analytic_op(programs, symbol_names,
File "/usr/local/lib/python3.8/dist-packages/tensorflow_quantum/core/ops/circuit_execution_ops.py", line 135, in <lambda>
op(programs, symbol_names, symbol_values, pauli_sums)
File "/usr/local/lib/python3.8/dist-packages/tensorflow_quantum/core/ops/tfq_simulate_ops.py", line 44, in tfq_simulate_expectation
return SIM_OP_MODULE.tfq_simulate_expectation(
File "<string>", line 79, in tfq_simulate_expectation
TypeError: Input 'pauli_sums' of 'TfqSimulateExpectation' Op has type float32 that does not match expected type of string.
Call arguments received:
• inputs=tf.Tensor(shape=(None,), dtype=string)
• symbol_names=tf.Tensor(shape=(22,), dtype=string)
• symbol_values=tf.Tensor(shape=(None, 22), dtype=float32)
• operators=tf.Tensor(shape=(None, 0), dtype=float32)
• repetitions=None
• initializer=<keras.initializers.initializers_v2.RandomUniform object at 0x7f856033a700>
Call arguments received:
• inputs=['tf.Tensor(shape=(None,), dtype=string)', 'tf.Tensor(shape=(None, 22), dtype=float32)']
Call arguments received:
• inputs=tf.Tensor(shape=(None, 2), dtype=float32)