ChoiceParameter with list of ints: TypeError: Object of type int32 is not JSON serializable

[BCJuan]

Hi,

First of all thank you for this awesome project.

Regarding the error: when trying to input a set of integers to a ChoiceParameter with parameter_type=ParameterType.INT the following error appears:

TypeError: Object of type int32 is not JSON serializable

The problem seems to occur at file arm.py and at function md5hash where the parameters are dumped to a JSON parameters_str = json.dumps(parameters, sort_keys=True)

To reproduce:

    range_x = ChoiceParameter(name='x', values=[1,5,10],
                              parameter_type=ParameterType.INT)
    space = SearchSpace(parameters=[range_x])
    experiment = Experiment(name="experiment_one_cell",
                            search_space=space)
    sobol = Models.SOBOL(search_space=experiment.search_space)
    generator_run = sobol.gen(100)

I have tried to make the list a set, but the problem seems to be in the parameter type definition. When changing to ParameterType.STRING and casting values to strings the problem does not exist.

I know this is not an important error, but I state it here just so it is somewhere defined.

Thank you .

UPDATE: indeed this is strange since there is already a conversion from numpy to python in function md5hash:

        for k, v in parameters.items():
            parameters[k] = numpy_type_to_python_type(v)

But it does not seem to work.

[ldworkin]

Hi @BCJuan ! Thanks for reporting this issue. I'm having trouble reproducing though. This is what I ran:

from ax import *

    range_x = ChoiceParameter(name='x', values=[1,5,10],
                              parameter_type=ParameterType.INT)
    space = SearchSpace(parameters=[range_x])
    experiment = Experiment(name="experiment_one_cell",
                            search_space=space)
    sobol = Models.SOBOL(search_space=experiment.search_space)
    generator_run = sobol.gen(100)

However, that completed successfully. Am I missing something?

[BCJuan]

Hi,

I still havethe problem if I use your code. It is my fault, I have checked the datatype and mine are numpy.int32

The function numpy_type_to_python_type in typeutils.py only catches np.int64 and numpy.float64.

I suppose is mandatory to use 64 bit data types.

Apologies for the time spent.

Best

[ldworkin]

Oh interesting! We can fix it to work with np.int32 and np.float32. Thanks for catching this!

[ldworkin]

Actually I believe this was already fixed! What version of Ax are you using?

see:
7904aa2#diff-0befb5b9d1a4f64449eba6e50b2d2b0d

[BCJuan]

My fault I am using 0.1.3. Closing the issue. Thanks!

[ldworkin]

Great!