AttributeError: 'Sum' object has no attribute 'gradient_x' when using sci-kit learn RBF for sci-kit optimize gp_minimize about scikit-optimize

[mahdiabdollahpour]

@mahdiabdollahpour try

from skopt.learning.gaussian_process.kernels import RBF

instead of

from sklearn.gaussian_process.kernels import RBF

It seems that Scikit-Optimize has a wrapper that implements gradient_x: https://github.com/scikit-optimize/scikit-optimize/blob/master/skopt/learning/gaussian_process/kernels.py#L68

It solves the problem.

[alipsgh]

@mahdiabdollahpour try

from skopt.learning.gaussian_process.kernels import RBF

instead of

from sklearn.gaussian_process.kernels import RBF

It seems that Scikit-Optimize has a wrapper that implements gradient_x: https://github.com/scikit-optimize/scikit-optimize/blob/master/skopt/learning/gaussian_process/kernels.py#L68

[alipsgh]

You may want to change the default Kernel from Matern to RBF (or any other) by editing the utils file: https://github.com/scikit-optimize/scikit-optimize/blob/master/skopt/utils.py#L380

if is_cat:
    other_kernel = HammingKernel(length_scale=np.ones(n_dims))
else:
    # other_kernel = Matern(
    #     length_scale=np.ones(n_dims),
    #     length_scale_bounds=[(0.01, 100)] * n_dims, nu=2.5)
    other_kernel = RBF(length_scale=np.ones(n_dims), length_scale_bounds=[(0.01, 100)] * n_dims)