TypeError: EvalfMixin.evalf() got an unexpected keyword argument 'real' hit in transpile

[cqc-melf]

Environment

• Qiskit version: 1.0.2
• Python version: 3.11, maybe more
• Operating system: linux and mac, maybe more

What is happening?

When transpiling the circuit shown below, we hit TypeError: EvalfMixin.evalf() got an unexpected keyword argument 'real'

qiskit/circuit/parameterexpression.py", line 528, in numeric
    real_expr = self._symbol_expr.evalf(real=True)
                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
TypeError: EvalfMixin.evalf() got an unexpected keyword argument 'real'

See

qiskit/qiskit/circuit/parameterexpression.py

Line 528 in 2cbbe2b

real_expr = self._symbol_expr.evalf(real=True)

How can we reproduce the issue?

from qiskit import transpile
from qiskit.circuit import (
    ParameterExpression,
)
from qiskit import transpile, QuantumCircuit
import qiskit.circuit.library.standard_gates as qiskit_gates
import sympy

symb_map = {}

params = [1.5707963267948966, 1.999999999999993, 10.995574287564276]

new_qiskit_c = QuantumCircuit(1)

half = ParameterExpression(symb_map, sympy.pi / 2)
new_qiskit_c.global_phase += -params[0] / 2 - params[2] / 2
new_qiskit_c.append(
            qiskit_gates.UGate(params[1], params[0] - half, params[2] + half),
            qargs=[0],
)

qc_transpiled_again = transpile(new_qiskit_c, basis_gates=["sx", "rz", "cx", "x"])

What should happen?

No error should show up and the transpile should work?

Any suggestions?

It might be possible to use the chop parameter instead of real, but I am not sure what the intended result should be.
More details at: https://docs.sympy.org/latest/modules/core.html#sympy.core.evalf.EvalfMixin.evalf

[cqc-melf]

If you need a more detailed error message or more details on other packages I am running this with, please let me know.

[jakelishman]

Thanks for the report!

The problem is that you've got a direct Sympy pi instance in ParameterExpression there. We stopped using Sympy entirely for ParameterExpression in #10902 a little while back - before that, we'd dynamically use either symengine or sympy. If you're manually constructing ParameterExpression, you'll need to convert the symbols and the inner expression to symengine constructs first, but that should ideally just be a call to symengine.sympify.

[cqc-melf]

Thank you for your help! That solved the problem :)