Trying to set 0 parameters for external functions. External function has 42 parameters

tudoroancea · October 19, 2022, 1:33pm

Hello there,

I tried creating an OCP with parametric cost functions, but when I tried to set the parameters using
AcadosOcp.set(), I got the following error:

acados_update_params: trying to set 0 parameters for external functions. External function has 17 parameters. Exiting.

I actually got the same one when I ran acados/examples/acados_python/tests/test_parametric_nonlinear_constrain_h.py.

Is that normal ?

Thanks a lot for your help.

Best,

Tudor

FreyJo · October 20, 2022, 7:34am

Hi Tudor,

the test definitely works for me and on our CI pipeline.
Did you modify the test in some way?
If so, can you clearly state what you modified?

Best,
Jonathan

tudoroancea · October 20, 2022, 10:17am

Hi,

I did not modify the file, but I have actually built acados from a slightly older commit (44ddf35db7fa11f26dfc36d5c9b0f3e30343530e, posted on sept 28) as I had trouble building acados with the latest commit. Should I try to ?

Best,

Tudor

P.S.: I should mention I am using acados on a M2 Mac, so maybe there are some deeper bugs coming from that

FreyJo · October 20, 2022, 11:17am

It might really be specific to your system.
Somehow
value_.shape[0] is 0 for you in this line:

github.com

acados/acados/blob/01d25216c4e32e8e6746f8dc6963a2096f1de353/interfaces/acados_template/acados_template/acados_ocp_solver.py#L1533


      
          
          
stage = c_int(stage_)
          
          
# treat parameters separately
          if field_ == 'p':
              getattr(self.shared_lib, f"{self.model_name}_acados_update_params").argtypes = [c_void_p, c_int, POINTER(c_double)]
              getattr(self.shared_lib, f"{self.model_name}_acados_update_params").restype = c_int
          
          
    value_data = cast(value_.ctypes.data, POINTER(c_double))
          
          
    assert getattr(self.shared_lib, f"{self.model_name}_acados_update_params")(self.capsule, stage, value_data, value_.shape[0])==0
          else:
              if field_ not in constraints_fields + cost_fields + out_fields:
                  raise Exception(f"AcadosOcpSolver.set(): '{field}' is not a valid argument.\n"
                      f" Possible values are {constraints_fields + cost_fields + out_fields + ['p']}.")
          
          
    self.shared_lib.ocp_nlp_dims_get_from_attr.argtypes = \
                  [c_void_p, c_void_p, c_void_p, c_int, c_char_p]
              self.shared_lib.ocp_nlp_dims_get_from_attr.restype = c_int
          
          
    dims = self.shared_lib.ocp_nlp_dims_get_from_attr(self.nlp_config, \

I hope you can debug this a bit further on your system.

tudoroancea · October 20, 2022, 11:26am

I debugged the code to inspect value_.shape[0] and it is 42 just as it should be . Could the arguments not be in the right order ?

FreyJo · October 20, 2022, 4:11pm

I think this was the issue:

Please let me know if that solves it for you.

tudoroancea · October 21, 2022, 4:56pm

Yes everything runs as it should, thank you very much for your quick corrections