Refer to Trotter Evolution in the video "Time Evolution with Qiskit Nature & Opflow"

[OuCheng-Fu]

Dear Everyone,

 I asked about how to implement Quantum Imaginary Time Evolution on IBM Qiskit, and I tried to implement Trotter Time Evolution by referencing this video ([Time Evolution with Qiskit Nature & Opflow - YouTube](https://www.youtube.com/watch?v=PY6PWondOeQ&list=LL&index=1)). At 7:23 of this video, the author tries to implement the trotter evolution of Ising model by the codes in the first picture; however, when I try to implement it on qiskit, it raises two errors: one is for time range: int object is not iterable and another one is "name 'param_bind' is not defined", like the latter 2 pictures I attached. What may be wrong in this process?

                                                                   Sincerely,

                                                                   Ou, Cheng-Fu

                                                                   2023/5/13

[Raghav-Bell]

As per documentation bind_parameters({parameter: parameter_value}) bind_parameters takes dictionary as input.Here param_bind refers to dictionary. ref: Qiskit documentation . As per tutorial notebook param_bind is initialized in cell 11 as follow:
param_bind = { tau: 1, tau_def: 0.5 }
please check if you forgot to initialize it.

[OuCheng-Fu]

Thank you. I have checked it and solved this issue.