geopfa.extrapolation.build_matern32_kernel_global

build_matern32_kernel_global(X_stdized, Y_stdized, input_dim=2, lower_frac=0.02, upper_frac=0.2)[source]

Construct a Matern 3/2 kernel with ARD lengthscales constrained by the global radius of the dataset in standardized space.

Parameters:

  • X_stdized (numpy.ndarray) – Standardized training coordinates, shape (N, 2).

  • Y_stdized (numpy.ndarray) – Standardized training targets, shape (N, 1).

  • input_dim (int, optional) – Dimensionality of the input space. Default is 2.

  • lower_frac (float, optional) – Fraction of the global radius used for the lower lengthscale bound.

  • upper_frac (float, optional) – Fraction of the global radius used for the upper lengthscale bound.

Returns:

(GPy.kern.Matern32, dict) – The Matern 3/2 kernel and a dictionary of initialization values and bound settings.

Notes

  • Variance is initialized to half the variance of Y and given a Gamma prior, matching the original implementation.

  • Lengthscales are constrained to dataset-scaled bounds.