Bug when using memory_warm_start with non-numerical search space

[SimonBlanke]

There is a bug in v3.0.2 when using the memory_warm_start and a non-numerical search space. This can be reproduced in the following example:

import pandas as pd
from hyperactive import Hyperactive

def dummy_function(opt):
    return 1

def func1():
    pass

search_space = {
    "obj1": [func1],
}

mem_df = pd.DataFrame([[func1, 1], [func1, 1], [func1, 1]], columns=["obj1", "score"])

hyper = Hyperactive()
hyper.add_search(dummy_function, search_space, n_iter=15, memory_warm_start=mem_df)
hyper.run()

[SimonBlanke]

The bug was caused by a missing conversion of the "memory_warm_start" dataframe from the hyperactive search space to the gradient-free-optimizers search space. Gradient-free-optimizers cannot handle non-numerical search spaces.

This bug was resolved in 5db63de by introducing a new class that handles the conversions of parameters and results between hyperactive and gradient-free-optimizers.
The new code is tested in 0519c53.

The fixed version is available in v3.0.3