Objective function is returning undefined values at initial point. FSOLVE cannot continue

I call "fsolve" function by using an interpreted MATLAB Function block in simulink.However, during simulation error occurs: "Objective function is returning undefined values at initial point. FSOLVE cannot continue". How can I solve the problem? Can anyone help me?

Answer 1

[Matt J]

To investigate what the objective function is complaining about, evaluate the initial point yourself manually and inspect the result.

[huan tu]

I had a trial using your method, i think the initial values were correct. Since there is an algebraic loop contained in the simulink, when i add a memory block in the loop, the warning "Objective function is returning undefined values at initial point. FSOLVE cannot continue" disapear, but the simulation is wrong. however, when i delete the memory block, the same warning takes place. So could you tell me some solutions? Thanks a lot!