storing the weights used by scipy griddata for re-use

Question

I am trying to interpolate data from an unstructured mesh M1 to another unstructured mesh M2. For this, scipy.interpolate.griddata

Answer 1

A solution is to use the LinearNDInterpolator Scipy function with a pre-computed Delaunay triangulation:

from scipy.spatial import Delaunay
from scipy.interpolate import LinearNDInterpolator

tri = Delaunay(mesh1)  # Compute the triangulation

# Perform the interpolation with the given values:
interpolator = LinearNDInterpolator(tri, values_mesh1)
values_mesh2 = interpolator(mesh2)

mesh1 is a (number of points * dim) array.

Note: CloughTocher2DInterpolator could be used for non-linear interpolation. griddata uses either LinearNDInterpolator or CloughTocher2DInterpolator.